Fourier coefficients of monstrous McKay–Thompson series

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Numbers
$g$
$n$ 
$c_g(n)$
1A:
equals: $q^n$ coefficients of the $j$-invariant, $n\geq1$
comment: The identity class: $T_{1A}=j-744$. For every $n\geq1$, its coefficient equals the coefficient of $q^n$ in $j$; this single reference covers the whole positive-exponent family.
2A
1:
4372
2A
2:
96256
2A
3:
1240002
2A
4:
10698752
2A
5:
74428120
2A
6:
431529984
2A
7:
2206741887
2A
8:
10117578752
2A
9:
42616961892
2A
10:
166564106240
2A
11:
611800208702
2A
12:
2125795885056
2A
13:
7040425608760
2A
14:
22327393665024
2A
15:
68134255043715
2A
16:
200740384538624
2A
17:
572950514538856
2A
18:
1588198806411264
2A
19:
4286153037862594
2A
20:
11283613372743680
2A
21:
29030493318777216
2A
22:
73105649849655296
2A
23:
180454128099240060
2A
24:
437155796944945152
2A
25:
1040545340935546700
2A
26:
2436001535686266880
2A
27:
5614282459787463036
2A
28:
12748902531008430080
2A
29:
28546382905646406648
2A
30:
63071424165763399680
2B
1:
276
2B
2:
-2048
2B
3:
11202
2B
4:
-49152
2B
5:
184024
2B
6:
-614400
2B
7:
1881471
2B
8:
-5373952
2B
9:
14478180
2B
10:
-37122048
2B
11:
91231550
2B
12:
-216072192
2B
13:
495248952
2B
14:
-1102430208
2B
15:
2390434947
2B
16:
-5061476352
2B
17:
10487167336
2B
18:
-21301241856
2B
19:
42481784514
2B
20:
-83300614144
2B
21:
160791890304
2B
22:
-305854488576
2B
23:
573872089212
2B
24:
-1063005978624
2B
25:
1945403602764
2B
26:
-3519965179904
2B
27:
6300794030460
2B
28:
-11164248047616
2B
29:
19591528119288
2B
30:
-34065932304384
3A
1:
783
3A
2:
8672
3A
3:
65367
3A
4:
371520
3A
5:
1741655
3A
6:
7161696
3A
7:
26567946
3A
8:
90521472
3A
9:
288078201
3A
10:
864924480
3A
11:
2469235686
3A
12:
6748494912
3A
13:
17746495281
3A
14:
45086909440
3A
15:
111066966315
3A
16:
266057139456
3A
17:
621284327856
3A
18:
1417338712800
3A
19:
3164665156308
3A
20:
6927097095040
3A
21:
14885655834663
3A
22:
31443042526848
3A
23:
65359285616037
3A
24:
133830265378176
3A
25:
270183001640175
3A
26:
538235428926784
3A
27:
1058813313902073
3A
28:
2058220759689216
3A
29:
3956007498445832
3A
30:
7522464148223040
3B
1:
54
3B
2:
-76
3B
3:
-243
3B
4:
1188
3B
5:
-1384
3B
6:
-2916
3B
7:
11934
3B
8:
-11580
3B
9:
-21870
3B
10:
79704
3B
11:
-71022
3B
12:
-123444
3B
13:
421308
3B
14:
-352544
3B
15:
-581013
3B
16:
1885572
3B
17:
-1510236
3B
18:
-2388204
3B
19:
7469928
3B
20:
-5777672
3B
21:
-8852004
3B
22:
26869968
3B
23:
-20218587
3B
24:
-30177684
3B
25:
89408826
3B
26:
-65743304
3B
27:
-96033357
3B
28:
278737632
3B
29:
-201031888
3B
30:
-288281592
3C
1:
0
3C
2:
248
3C
3:
0
3C
4:
0
3C
5:
4124
3C
6:
0
3C
7:
0
3C
8:
34752
3C
9:
0
3C
10:
0
3C
11:
213126
3C
12:
0
3C
13:
0
3C
14:
1057504
3C
15:
0
3C
16:
0
3C
17:
4530744
3C
18:
0
3C
19:
0
3C
20:
17333248
3C
21:
0
3C
22:
0
3C
23:
60655377
3C
24:
0
3C
25:
0
3C
26:
197230000
3C
27:
0
3C
28:
0
3C
29:
603096260
3C
30:
0
4A
1:
276
4A
2:
2048
4A
3:
11202
4A
4:
49152
4A
5:
184024
4A
6:
614400
4A
7:
1881471
4A
8:
5373952
4A
9:
14478180
4A
10:
37122048
4A
11:
91231550
4A
12:
216072192
4A
13:
495248952
4A
14:
1102430208
4A
15:
2390434947
4A
16:
5061476352
4A
17:
10487167336
4A
18:
21301241856
4A
19:
42481784514
4A
20:
83300614144
4A
21:
160791890304
4A
22:
305854488576
4A
23:
573872089212
4A
24:
1063005978624
4A
25:
1945403602764
4A
26:
3519965179904
4A
27:
6300794030460
4A
28:
11164248047616
4A
29:
19591528119288
4A
30:
34065932304384
4B
1:
52
4B
2:
0
4B
3:
834
4B
4:
0
4B
5:
4760
4B
6:
0
4B
7:
24703
4B
8:
0
4B
9:
94980
4B
10:
0
4B
11:
343998
4B
12:
0
4B
13:
1077496
4B
14:
0
4B
15:
3222915
4B
16:
0
4B
17:
8844712
4B
18:
0
4B
19:
23381058
4B
20:
0
4B
21:
58359168
4B
22:
0
4B
23:
141244796
4B
24:
0
4B
25:
327974700
4B
26:
0
4B
27:
742169724
4B
28:
0
4B
29:
1627202744
4B
30:
0
4C
1:
20
4C
2:
0
4C
3:
-62
4C
4:
0
4C
5:
216
4C
6:
0
4C
7:
-641
4C
8:
0
4C
9:
1636
4C
10:
0
4C
11:
-3778
4C
12:
0
4C
13:
8248
4C
14:
0
4C
15:
-17277
4C
16:
0
4C
17:
34664
4C
18:
0
4C
19:
-66878
4C
20:
0
4C
21:
125312
4C
22:
0
4C
23:
-229252
4C
24:
0
4C
25:
409676
4C
26:
0
4C
27:
-716420
4C
28:
0
4C
29:
1230328
4C
30:
0
4D
1:
-12
4D
2:
0
4D
3:
66
4D
4:
0
4D
5:
-232
4D
6:
0
4D
7:
639
4D
8:
0
4D
9:
-1596
4D
10:
0
4D
11:
3774
4D
12:
0
4D
13:
-8328
4D
14:
0
4D
15:
17283
4D
16:
0
4D
17:
-34520
4D
18:
0
4D
19:
66882
4D
20:
0
4D
21:
-125568
4D
22:
0
4D
23:
229244
4D
24:
0
4D
25:
-409236
4D
26:
0
4D
27:
716412
4D
28:
0
4D
29:
-1231048
4D
30:
0
5A
1:
134
5A
2:
760
5A
3:
3345
5A
4:
12256
5A
5:
39350
5A
6:
114096
5A
7:
307060
5A
8:
776000
5A
9:
1867170
5A
10:
4298600
5A
11:
9540169
5A
12:
20487360
5A
13:
42756520
5A
14:
86967184
5A
15:
172859325
5A
16:
336450560
5A
17:
642489660
5A
18:
1205572920
5A
19:
2226005750
5A
20:
4049168800
5A
21:
7264172196
5A
22:
12864273920
5A
23:
22507811570
5A
24:
38936117376
5A
25:
66640520250
5A
26:
112915572144
5A
27:
189513785625
5A
28:
315222537280
5A
29:
519857920876
5A
30:
850404637200
5B
1:
9
5B
2:
10
5B
3:
-30
5B
4:
6
5B
5:
-25
5B
6:
96
5B
7:
60
5B
8:
-250
5B
9:
45
5B
10:
-150
5B
11:
544
5B
12:
360
5B
13:
-1230
5B
14:
184
5B
15:
-675
5B
16:
2310
5B
17:
1410
5B
18:
-4830
5B
19:
750
5B
20:
-2450
5B
21:
8196
5B
22:
4920
5B
23:
-16180
5B
24:
2376
5B
25:
-7875
5B
26:
25644
5B
27:
15000
5B
28:
-48720
5B
29:
7126
5B
30:
-22800
6A
1:
79
6A
2:
352
6A
3:
1431
6A
4:
4160
6A
5:
13015
6A
6:
31968
6A
7:
81162
6A
8:
183680
6A
9:
412857
6A
10:
864320
6A
11:
1805030
6A
12:
3564864
6A
13:
7000753
6A
14:
13243392
6A
15:
24805035
6A
16:
45168896
6A
17:
81544240
6A
18:
143832672
6A
19:
251550676
6A
20:
432030080
6A
21:
735553575
6A
22:
1233715328
6A
23:
2052941733
6A
24:
3372465024
6A
25:
5499116975
6A
26:
8869747264
6A
27:
14205516345
6A
28:
22536833024
6A
29:
35522228616
6A
30:
55521080640
6B
1:
78
6B
2:
364
6B
3:
1365
6B
4:
4380
6B
5:
12520
6B
6:
32772
6B
7:
80094
6B
8:
185276
6B
9:
409578
6B
10:
871272
6B
11:
1792754
6B
12:
3582708
6B
13:
6977100
6B
14:
13277472
6B
15:
24747867
6B
16:
45267324
6B
17:
81389908
6B
18:
144048396
6B
19:
251265288
6B
20:
432425864
6B
21:
734953116
6B
22:
1234647216
6B
23:
2051576037
6B
24:
3374318100
6B
25:
5496690786
6B
26:
8873025160
6B
27:
14200826811
6B
28:
22543648032
6B
29:
35512689984
6B
30:
55533745080
6C
1:
15
6C
2:
-32
6C
3:
87
6C
4:
-192
6C
5:
343
6C
6:
-672
6C
7:
1290
6C
8:
-2176
6C
9:
3705
6C
10:
-6336
6C
11:
10214
6C
12:
-16320
6C
13:
25905
6C
14:
-39936
6C
15:
61227
6C
16:
-92928
6C
17:
138160
6C
18:
-204576
6C
19:
300756
6C
20:
-435328
6C
21:
626727
6C
22:
-897408
6C
23:
1271205
6C
24:
-1790592
6C
25:
2508783
6C
26:
-3487424
6C
27:
4824825
6C
28:
-6641664
6C
29:
9083400
6C
30:
-12371904
6D
1:
-2
6D
2:
28
6D
3:
-27
6D
4:
-52
6D
5:
136
6D
6:
-108
6D
7:
-162
6D
8:
620
6D
9:
-486
6D
10:
-760
6D
11:
1970
6D
12:
-1404
6D
13:
-1940
6D
14:
6048
6D
15:
-4293
6D
16:
-6100
6D
17:
15796
6D
18:
-10692
6D
19:
-14264
6D
20:
40232
6D
21:
-27108
6D
22:
-36496
6D
23:
93285
6D
24:
-61020
6D
25:
-79054
6D
26:
211624
6D
27:
-137781
6D
28:
-179296
6D
29:
451680
6D
30:
-288360
6E
1:
6
6E
2:
4
6E
3:
-3
6E
4:
-12
6E
5:
-8
6E
6:
12
6E
7:
30
6E
8:
20
6E
9:
-30
6E
10:
-72
6E
11:
-46
6E
12:
60
6E
13:
156
6E
14:
96
6E
15:
-117
6E
16:
-300
6E
17:
-188
6E
18:
228
6E
19:
552
6E
20:
344
6E
21:
-420
6E
22:
-1008
6E
23:
-603
6E
24:
732
6E
25:
1770
6E
26:
1048
6E
27:
-1245
6E
28:
-2976
6E
29:
-1776
6E
30:
2088
6F
1:
0
6F
2:
-8
6F
3:
0
6F
4:
0
6F
5:
28
6F
6:
0
6F
7:
0
6F
8:
-64
6F
9:
0
6F
10:
0
6F
11:
134
6F
12:
0
6F
13:
0
6F
14:
-288
6F
15:
0
6F
16:
0
6F
17:
568
6F
18:
0
6F
19:
0
6F
20:
-1024
6F
21:
0
6F
22:
0
6F
23:
1809
6F
24:
0
6F
25:
0
6F
26:
-3152
6F
27:
0
6F
28:
0
6F
29:
5316
6F
30:
0
7A
1:
51
7A
2:
204
7A
3:
681
7A
4:
1956
7A
5:
5135
7A
6:
12360
7A
7:
28119
7A
8:
60572
7A
9:
125682
7A
10:
251040
7A
11:
487426
7A
12:
920568
7A
13:
1699611
7A
14:
3070508
7A
15:
5445510
7A
16:
9490116
7A
17:
16283793
7A
18:
27537708
7A
19:
45959775
7A
20:
75760640
7A
21:
123471327
7A
22:
199081632
7A
23:
317814988
7A
24:
502608456
7A
25:
787889775
7A
26:
1224834672
7A
27:
1889206080
7A
28:
2892264900
7A
29:
4396716468
7A
30:
6638862720
7B
1:
2
7B
2:
8
7B
3:
-5
7B
4:
-4
7B
5:
-10
7B
6:
12
7B
7:
-7
7B
8:
8
7B
9:
46
7B
10:
-36
7B
11:
-26
7B
12:
-44
7B
13:
46
7B
14:
-28
7B
15:
42
7B
16:
188
7B
17:
-132
7B
18:
-96
7B
19:
-167
7B
20:
172
7B
21:
-98
7B
22:
120
7B
23:
596
7B
24:
-420
7B
25:
-286
7B
26:
-492
7B
27:
496
7B
28:
-280
7B
29:
368
7B
30:
1680
8A
1:
36
8A
2:
128
8A
3:
386
8A
4:
1024
8A
5:
2488
8A
6:
5632
8A
7:
12031
8A
8:
24576
8A
9:
48308
8A
10:
91904
8A
11:
170110
8A
12:
307200
8A
13:
542872
8A
14:
941056
8A
15:
1602819
8A
16:
2686976
8A
17:
4439688
8A
18:
7238272
8A
19:
11657090
8A
20:
18561024
8A
21:
29242240
8A
22:
45617664
8A
23:
70507772
8A
24:
108036096
8A
25:
164192188
8A
26:
247620352
8A
27:
370726652
8A
28:
551215104
8A
29:
814216536
8A
30:
1195226112
8B
1:
12
8B
2:
0
8B
3:
66
8B
4:
0
8B
5:
232
8B
6:
0
8B
7:
639
8B
8:
0
8B
9:
1596
8B
10:
0
8B
11:
3774
8B
12:
0
8B
13:
8328
8B
14:
0
8B
15:
17283
8B
16:
0
8B
17:
34520
8B
18:
0
8B
19:
66882
8B
20:
0
8B
21:
125568
8B
22:
0
8B
23:
229244
8B
24:
0
8B
25:
409236
8B
26:
0
8B
27:
716412
8B
28:
0
8B
29:
1231048
8B
30:
0
8C
1:
0
8C
2:
0
8C
3:
26
8C
4:
0
8C
5:
0
8C
6:
0
8C
7:
79
8C
8:
0
8C
9:
0
8C
10:
0
8C
11:
326
8C
12:
0
8C
13:
0
8C
14:
0
8C
15:
755
8C
16:
0
8C
17:
0
8C
18:
0
8C
19:
2106
8C
20:
0
8C
21:
0
8C
22:
0
8C
23:
4460
8C
24:
0
8C
25:
0
8C
26:
0
8C
27:
10284
8C
28:
0
8C
29:
0
8C
30:
0
8D
1:
-4
8D
2:
0
8D
3:
2
8D
4:
0
8D
5:
8
8D
6:
0
8D
7:
-1
8D
8:
0
8D
9:
-20
8D
10:
0
8D
11:
-2
8D
12:
0
8D
13:
40
8D
14:
0
8D
15:
3
8D
16:
0
8D
17:
-72
8D
18:
0
8D
19:
2
8D
20:
0
8D
21:
128
8D
22:
0
8D
23:
-4
8D
24:
0
8D
25:
-220
8D
26:
0
8D
27:
-4
8D
28:
0
8D
29:
360
8D
30:
0
8E
1:
4
8E
2:
0
8E
3:
2
8E
4:
0
8E
5:
-8
8E
6:
0
8E
7:
-1
8E
8:
0
8E
9:
20
8E
10:
0
8E
11:
-2
8E
12:
0
8E
13:
-40
8E
14:
0
8E
15:
3
8E
16:
0
8E
17:
72
8E
18:
0
8E
19:
2
8E
20:
0
8E
21:
-128
8E
22:
0
8E
23:
-4
8E
24:
0
8E
25:
220
8E
26:
0
8E
27:
-4
8E
28:
0
8E
29:
-360
8E
30:
0
8F
1:
0
8F
2:
0
8F
3:
-6
8F
4:
0
8F
5:
0
8F
6:
0
8F
7:
15
8F
8:
0
8F
9:
0
8F
10:
0
8F
11:
-26
8F
12:
0
8F
13:
0
8F
14:
0
8F
15:
51
8F
16:
0
8F
17:
0
8F
18:
0
8F
19:
-102
8F
20:
0
8F
21:
0
8F
22:
0
8F
23:
172
8F
24:
0
8F
25:
0
8F
26:
0
8F
27:
-276
8F
28:
0
8F
29:
0
8F
30:
0
9A
1:
27
9A
2:
86
9A
3:
243
9A
4:
594
9A
5:
1370
9A
6:
2916
9A
7:
5967
9A
8:
11586
9A
9:
21870
9A
10:
39852
9A
11:
71052
9A
12:
123444
9A
13:
210654
9A
14:
352480
9A
15:
581013
9A
16:
942786
9A
17:
1510254
9A
18:
2388204
9A
19:
3734964
9A
20:
5777788
9A
21:
8852004
9A
22:
13434984
9A
23:
20218395
9A
24:
30177684
9A
25:
44704413
9A
26:
65743348
9A
27:
96033357
9A
28:
139368816
9A
29:
201032186
9A
30:
288281592
9B
1:
0
9B
2:
5
9B
3:
0
9B
4:
0
9B
5:
-7
9B
6:
0
9B
7:
0
9B
8:
3
9B
9:
0
9B
10:
0
9B
11:
15
9B
12:
0
9B
13:
0
9B
14:
-32
9B
15:
0
9B
16:
0
9B
17:
9
9B
18:
0
9B
19:
0
9B
20:
58
9B
21:
0
9B
22:
0
9B
23:
-96
9B
24:
0
9B
25:
0
9B
26:
22
9B
27:
0
9B
28:
0
9B
29:
149
9B
30:
0
10A
1:
22
10A
2:
56
10A
3:
177
10A
4:
352
10A
5:
870
10A
6:
1584
10A
7:
3412
10A
8:
5952
10A
9:
11442
10A
10:
19240
10A
11:
34377
10A
12:
56256
10A
13:
95560
10A
14:
151824
10A
15:
247965
10A
16:
385024
10A
17:
609756
10A
18:
927864
10A
19:
1431094
10A
20:
2139680
10A
21:
3228516
10A
22:
4752896
10A
23:
7038610
10A
24:
10215552
10A
25:
14885450
10A
26:
21330480
10A
27:
30643161
10A
28:
43407680
10A
29:
61571148
10A
30:
86305680
10B
1:
6
10B
2:
-8
10B
3:
17
10B
4:
-32
10B
5:
54
10B
6:
-80
10B
7:
116
10B
8:
-192
10B
9:
290
10B
10:
-408
10B
11:
585
10B
12:
-832
10B
13:
1192
10B
14:
-1648
10B
15:
2237
10B
16:
-3072
10B
17:
4156
10B
18:
-5576
10B
19:
7414
10B
20:
-9824
10B
21:
12964
10B
22:
-16896
10B
23:
22002
10B
24:
-28544
10B
25:
36794
10B
26:
-47184
10B
27:
60185
10B
28:
-76736
10B
29:
97388
10B
30:
-122864
10C
1:
-3
10C
2:
6
10C
3:
2
10C
4:
2
10C
5:
-5
10C
6:
-16
10C
7:
12
10C
8:
2
10C
9:
17
10C
10:
-10
10C
11:
-48
10C
12:
56
10C
13:
10
10C
14:
24
10C
15:
-35
10C
16:
-126
10C
17:
106
10C
18:
14
10C
19:
94
10C
20:
-70
10C
21:
-284
10C
22:
296
10C
23:
60
10C
24:
152
10C
25:
-175
10C
26:
-620
10C
27:
536
10C
28:
80
10C
29:
398
10C
30:
-320
10D
1:
21
10D
2:
62
10D
3:
162
10D
4:
378
10D
5:
819
10D
6:
1680
10D
7:
3276
10D
8:
6138
10D
9:
11145
10D
10:
19662
10D
11:
33840
10D
12:
57048
10D
13:
94362
10D
14:
153432
10D
15:
245757
10D
16:
388218
10D
17:
605466
10D
18:
933414
10D
19:
1423614
10D
20:
2149586
10D
21:
3215844
10D
22:
4769544
10D
23:
7016572
10D
24:
10243896
10D
25:
14848809
10D
26:
21378276
10D
27:
30582360
10D
28:
43484304
10D
29:
61473438
10D
30:
86428896
10E
1:
1
10E
2:
2
10E
3:
2
10E
4:
-2
10E
5:
-1
10E
6:
0
10E
7:
-4
10E
8:
-2
10E
9:
5
10E
10:
2
10E
11:
0
10E
12:
8
10E
13:
2
10E
14:
-8
10E
15:
-3
10E
16:
-2
10E
17:
-14
10E
18:
-6
10E
19:
14
10E
20:
6
10E
21:
4
10E
22:
24
10E
23:
12
10E
24:
-24
10E
25:
-11
10E
26:
-4
10E
27:
-40
10E
28:
-16
10E
29:
38
10E
30:
16
Definition
The entry is the signed coefficient $c_g(n)=\operatorname{Tr}(g\mid V_n^\natural)$ in the normalized Monster McKay–Thompson series $T_g(\tau)=q^{-1}+\sum_{n\geq1}c_g(n)q^n$, where $q=e^{2\pi i\tau}$ and $V_n^\natural$ is the degree-$n$ component of the moonshine module in the shifted grading [1].
Parameters
$g$
—   Monster conjugacy class (a Monster conjugacy class in the ATLAS notation)
$n$
—   Fourier exponent ($n\geq1$)
Formulas
(1)
$P_{2,g}(X)=X^2-2c_g(1)$ and $P_{3,g}(X)=X^3-3c_g(1)X-3c_g(2)$, where $P_{m,g}$ is the monic Hecke-type Faber polynomial.
(2)
$P_{m,g}(T_g(\tau))=\sum_{ad=m,\ a,d>0}\sum_{b=0}^{d-1}T_{g^a}((a\tau+b)/d)$ for $m\geq1$, where $P_{m,g}$ is the monic Faber polynomial and $g^a$ denotes the conjugacy class of the $a$th power. There is no factor $1/m$ [2], §8; [3], §§8–9.
(3)
For $p\in\{2,3,5,7\}$, put $e_p=24/(p-1)$ and $R_p(\tau)=(\eta(\tau)/\eta(p\tau))^{e_p}$, with $\eta(\tau)=q^{1/24}\prod_{r\geq1}(1-q^r)$. Then $T_{pB}=R_p+e_p$ and $T_{pA}=R_p+e_p+p^{12/(p-1)}/R_p$ [2], §6 and Table 3. Rectangular CM evaluations use the same normalization.
Comments
(4)
The grading is $V^\natural=\bigoplus_{n\geq-1}V_n^\natural$, with $\dim V_{-1}^\natural=1$ and $V_0^\natural=0$. The pole coefficient and the zero constant coefficient are not repeated as entries. A grading by conformal weight assigns weight $n+1$ to $V_n^\natural$ [1].
(5)
The identity class satisfies $T_{1A}=j-744$. Its positive Fourier coefficients equal those in the $j$-invariant expansion. The first $1A$ row references that whole family for $n\geq1$, without duplicating its entries.
(6)
The class labels are Monster conjugacy classes in the ATLAS notation [4]. These values are traces on graded representations, rather than individual irreducible character degrees. Negative traces and structural zeros are retained. Conway and Norton call the coefficient characters $H_n$; their Table 4 row $H_0$ is a Rademacher constant, not the constant coefficient of $T_g$ [2], §10.
(7)
The Hecke-type Faber polynomials $P_{m,g}(X)$ are the unique monic polynomials satisfying $P_{m,g}(T_g(\tau))=q^{-m}+O(q)$. Their coefficients are determined by the coefficients tabulated here. The class parameter selects the acting group element, while the entries always give the same graded-trace quantity.
Programs
(P1)
Sage
# Save generate.py, seeds.json and class-data.json from the attachments
# in the working directory.
# The output is an exact integer; the digits argument does not round it.
from generate import McKayThompsonCoefficients
generator = McKayThompsonCoefficients()
generator.value({'g': '2A', 'n': 30}, digits=100)
References
[1]
John F. R. Duncan, Michael J. Griffin and Ken Ono, Moonshine, Research in the Mathematical Sciences 2 (2015), article 11, §3. (arXiv)
[2]
John H. Conway and Simon P. Norton, Monstrous Moonshine, Bulletin of the London Mathematical Society 11 (1979), 308–339, §§6, 8, 10 and Tables 1a, 2, 3, 4. (doi) https://gwern.net/doc/math/1979-conway.pdf
[3]
Richard E. Borcherds, Monstrous moonshine and monstrous Lie superalgebras, Inventiones Mathematicae 109 (1992), 405–444, §§8–9. (doi) https://math.berkeley.edu/~reb/papers/monster/monster.pdf
Links
Similar tables
$q$-expansion of the $j$-invariant —   Its positive Fourier coefficients give the identity-class traces, referenced by the leading 1A row.
Hecke-type Faber polynomials —   These polynomial transforms of the same series are determined by their Fourier coefficients.
McKay–Thompson values at rectangular CM points —   These evaluate the same normalized series at principal rectangular CM arguments.
Degrees of sporadic-group irreducible characters —   The Monster degrees give dimensions of irreducible constituents of the graded moonshine representations.
Data properties
Entries are of type: integer
Table is complete: no (it holds every $1\leq n\leq30$ for all 32 nonidentity Monster classes of order at most 10: $2A,2B,3A,3B,3C,4A,4B,4C,4D,5A,5B,6A,6B,6C,6D,6E,6F,7A,7B,8A,8B,8C,8D,8E,8F,9A,9B,10A,10B,10C,10D,10E$. These noncanonical practical bounds cover a shared initial graded segment across all low-order classes, including prime and composite orders and sparse and dense series. Including the identity internally makes the selected classes closed under powers for verification. The exponent bound extends beyond the ten-term published controls while keeping entries short; the longest integer has 20 characters. A single leading $1A$ reference links to the $j$-invariant expansion for every $n\geq1$; those coefficients are not duplicated here)
How they were obtained:

Computed using exact integer arithmetic and the four coefficient recurrences in [3], §9, equation (9.1). Every division by two is checked for exact divisibility. The seeds at exponents 1, 2, 3 and 5 are transcribed from the scanned Table 4 in [2]; the squared-class data are frozen from GAP CTblLib 1.3.11 [4]. The identity-class series is computed internally from $j=E_4^3/\Delta$, using $E_4$ and $\Delta$.

more

All first-ten coefficients for the 32 stored classes and the identity agree with the scanned published controls. Character sums using the decompositions in [2], Table 1a, agree for exponents 1 through 5 in all 33 classes. Independent finite eta products agree with all 240 coefficients of the eight prime-order series. Triangular Laurent cancellation checks the replication relations at multipliers 3 and 5 through exponents 10 and 6, respectively, for every stored class. It also reconstructs all 171 overlapping Faber polynomials through degree 20. The identity coefficients agree with the separate $j$ expansion through exponent 30. Known-answer controls and deliberately incorrect signs and exponent offsets precede the comparisons. The attached checker repeats these tests on values read from the database.