Stirling polynomials $S_k(x)$
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Polynomials
$k$ 
$S_k(x)$
0:
1
1:
1/2*x + 1/2
2:
1/4*x^2 + 5/12*x + 1/6
3:
1/8*x^3 + 1/4*x^2 + 1/8*x
4:
1/16*x^4 + 1/8*x^3 + 1/48*x^2 - 3/40*x - 1/30
5:
1/32*x^5 + 5/96*x^4 - 5/96*x^3 - 13/96*x^2 - 1/16*x
6:
1/64*x^6 + 1/64*x^5 - 5/64*x^4 - 77/576*x^3 - 1/48*x^2 + 59/1008*x + 1/42
7:
1/128*x^7 - 7/96*x^5 - 49/576*x^4 + 91/1152*x^3 + 97/576*x^2 + 5/72*x
8:
1/256*x^8 - 1/192*x^7 - 7/128*x^6 - 7/288*x^5 + 1211/6912*x^4 + 407/1728*x^3 + 221/8640*x^2 - 193/2160*x - 1/30
9:
1/512*x^9 - 3/512*x^8 - 9/256*x^7 + 91/3840*x^6 + 1687/7680*x^5 + 93/512*x^4 - 197/960*x^3 - 671/1920*x^2 - 21/160*x
10:
1/1024*x^10 - 5/1024*x^9 - 5/256*x^8 + 77/1536*x^7 + 623/3072*x^6 + 115/9216*x^5 - 863/1536*x^4 - 1421/2304*x^3 - 5/128*x^2 + 691/3168*x + 5/66
11:
1/2048*x^11 - 11/3072*x^10 - 55/6144*x^9 + 11/192*x^8 + 2651/18432*x^7 - 1837/9216*x^6 - 5225/6144*x^5 - 2365/4608*x^4 + 3487/4608*x^3 + 413/384*x^2 + 3/8*x
12:
1/4096*x^12 - 5/2048*x^11 - 11/4096*x^10 + 319/6144*x^9 + 869/12288*x^8 - 759/2048*x^7 - 98219/110592*x^6 + 4235/18432*x^5 + 66715/27648*x^4 + 51977/23040*x^3 + 3149/60480*x^2 - 11247/14560*x - 691/2730
13:
1/8192*x^13 - 13/8192*x^12 + 13/24576*x^11 + 1001/24576*x^10 + 143/24576*x^9 - 232661/516096*x^8 - 4795219/7741440*x^7 + 1657799/1105920*x^6 + 2318173/552960*x^5 + 513851/276480*x^4 - 3596333/967680*x^3 - 1110689/241920*x^2 - 7601/5040*x
14:
1/16384*x^14 - 49/49152*x^13 + 91/49152*x^12 + 7007/245760*x^11 - 29029/737280*x^10 - 21307/49152*x^9 - 289003/2211840*x^8 + 18737719/6635520*x^7 + 7794787/1658880*x^6 - 2241967/829440*x^5 - 5567081/414720*x^4 - 4576061/414720*x^3 + 14827/103680*x^2 + 16139/4320*x + 7/6
15:
1/32768*x^15 - 5/8192*x^14 + 35/16384*x^13 + 2639/147456*x^12 - 1547/24576*x^11 - 50765/147456*x^10 + 183469/442368*x^9 + 1611467/442368*x^8 + 2450305/884736*x^7 - 5430607/442368*x^6 - 5744219/221184*x^5 - 913789/110592*x^4 + 648949/27648*x^3 + 29921/1152*x^2 + 65/8*x
16:
1/65536*x^16 - 3/8192*x^15 + 95/49152*x^14 + 91/9216*x^13 - 20293/294912*x^12 - 2717/12288*x^11 + 380237/442368*x^10 + 99385/27648*x^9 - 9007999/5308416*x^8 - 5339789/221184*x^7 - 736853/24576*x^6 + 769285/27648*x^5 + 52181287/552960*x^4 + 321517/4608*x^3 - 66293/20736*x^2 - 347341/14688*x - 3617/510
17:
1/131072*x^17 - 85/393216*x^16 + 51/32768*x^15 + 1309/294912*x^14 - 111503/1769472*x^13 - 173927/1769472*x^12 + 108953/98304*x^11 + 7062055/2654208*x^10 - 80283775/10616832*x^9 - 1729577603/53084160*x^8 - 17489719/1658880*x^7 + 766204229/6635520*x^6 + 660607369/3317760*x^5 + 140907917/3317760*x^4 - 8562679/46080*x^3 - 4336337/23040*x^2 - 3617/64*x
18:
1/262144*x^18 - 33/262144*x^17 + 153/131072*x^16 + 221/196608*x^15 - 20179/393216*x^14 + 221/131072*x^13 + 841789/737280*x^12 + 3313453/2949120*x^11 - 152951227/11796480*x^10 - 10085915567/318504960*x^9 + 714638197/17694720*x^8 + 3162255493/13271040*x^7 + 10505099/46080*x^6 - 410886073/1327104*x^5 - 302682773/368640*x^4 - 2417398637/4354560*x^3 + 20498021/483840*x^2 + 218052091/1149120*x + 43867/798
19:
1/524288*x^19 - 19/262144*x^18 + 437/524288*x^17 - 323/491520*x^16 - 149549/3932160*x^15 + 81719/1179648*x^14 + 11793053/11796480*x^13 - 1734187/2949120*x^12 - 1143551461/70778880*x^11 - 5876093197/318504960*x^10 + 513442731217/4459069440*x^9 + 61504274653/185794560*x^8 - 3104327483/185794560*x^7 - 1680599039/1327104*x^6 - 24689670707/13271040*x^5 - 1563405709/6967296*x^4 + 4494370181/2488320*x^3 + 19594583/11520*x^2 + 745739/1512*x
20:
1/1048576*x^20 - 65/1572864*x^19 + 1805/3145728*x^18 - 2261/1572864*x^17 - 121771/4718592*x^16 + 1732895/16515072*x^15 + 24825457/33030144*x^14 - 14641913/7077888*x^13 - 152528675/9437184*x^12 + 680863651/127401984*x^11 + 1015992437629/5350883328*x^10 + 801828182339/2675441664*x^9 - 39208296545/55738368*x^8 - 43572202903/15925248*x^7 - 32314359611/15925248*x^6 + 5444607417793/1393459200*x^5 + 1815290979443/209018880*x^4 + 283991612543/52254720*x^3 - 607681817/1064448*x^2 - 18784524793/9979200*x - 174611/330
21:
1/2097152*x^21 - 49/2097152*x^20 + 805/2097152*x^19 - 10241/6291456*x^18 - 6251/393216*x^17 + 120479/1048576*x^16 + 13273039/28311552*x^15 - 3199315/1048576*x^14 - 738354421/56623104*x^13 + 190047936715/5605687296*x^12 + 1308403256225/5605687296*x^11 + 35993435555/509607936*x^10 - 762535696813/424673280*x^9 - 27215774249/7077888*x^8 + 4250008483/2654208*x^7 + 12910570050283/796262400*x^6 + 8311577861809/398131200*x^5 + 3665539381/4976640*x^4 - 128833133063/6082560*x^3 - 71328391847/3801600*x^2 - 23223263/4400*x
22:
1/4194304*x^22 - 55/4194304*x^21 + 3157/12582912*x^20 - 19019/12582912*x^19 - 54131/6291456*x^18 + 2028763/18874368*x^17 + 11728453/56623104*x^16 - 194970875/56623104*x^15 - 871710785/113246208*x^14 + 303923002747/5096079360*x^13 + 1124746504037/5096079360*x^12 - 5488479812849/15288238080*x^11 - 1249125008747/424673280*x^10 - 11331369254557/3822059520*x^9 + 1305289773953/106168320*x^8 + 58136290940783/1592524800*x^7 + 328916159561/15925248*x^6 - 67624515746711/1194393600*x^5 - 15198170263/138240*x^4 - 4796904302521/74649600*x^3 + 19609193/2304*x^2 + 67430533733/2980800*x + 854513/138
23:
1/8388608*x^23 - 23/3145728*x^22 + 253/1572864*x^21 - 5313/4194304*x^20 - 278047/75497472*x^19 + 379753/4194304*x^18 - 4807/35389440*x^17 - 2805494989/849346560*x^16 - 5007004849/3397386240*x^15 + 193484597929/2548039680*x^14 + 549689116147/3822059520*x^13 - 13765722903649/15288238080*x^12 - 108131369737513/30576476160*x^11 + 533288632877/339738624*x^10 + 12896761584443/424673280*x^9 + 54068692472531/1061683200*x^8 - 395036620048477/9555148800*x^7 - 1153019519149003/4777574400*x^6 - 33156550213997/119439360*x^5 + 1264406584061/99532800*x^4 + 612140294039/2073600*x^3 + 42884916121/172800*x^2 + 543781/8*x
24:
1/16777216*x^24 - 17/4194304*x^23 + 851/8388608*x^22 - 93863/94371840*x^21 - 54901/83886080*x^20 + 2648657/37748736*x^19 - 39854837/283115520*x^18 - 24597419/8847360*x^17 + 9778740697/2264924160*x^16 + 403350623743/5096079360*x^15 + 156626119601/10192158720*x^14 - 3556808992681/2548039680*x^13 - 543457191427337/183458856960*x^12 + 157236667798331/15288238080*x^11 + 2280762988276091/45864714240*x^10 + 530276656409269/19110297600*x^9 - 4424655011910617/19110297600*x^8 - 896888976127001/1592524800*x^7 - 16667720756480383/71663616000*x^6 + 5629841337175471/5971968000*x^5 + 10303015964096693/6270566400*x^4 + 472027022290043/522547200*x^3 - 14505391013281/101088000*x^2 - 19098819511351/58968000*x - 236364091/2730
25:
1/33554432*x^25 - 75/33554432*x^24 + 3175/50331648*x^23 - 112585/150994944*x^22 + 302335/301989888*x^21 + 15224275/301989888*x^20 - 49396985/226492416*x^19 - 232634765/113246208*x^18 + 23685170575/2717908992*x^17 + 564960331985/8153726976*x^16 - 20550211235/150994944*x^15 - 266263559870185/158997676032*x^14 - 850609190721865/953986056192*x^13 + 1586065506783335/73383542784*x^12 + 524594688243635/9172942848*x^11 - 46307834639785279/642105999360*x^10 - 3043109925477985/5350883328*x^9 - 2722928693387705/3567255552*x^8 + 19520336549170627/20065812480*x^7 + 23790570574916621/5733089280*x^6 + 8672163370983461/2006581248*x^5 - 270154156186657/501645312*x^4 - 4372254451065077/905748480*x^3 - 439060121079173/113218560*x^2 - 27181870465/26208*x
26:
1/67108864*x^26 - 247/201326592*x^25 + 325/8388608*x^24 - 162955/301989888*x^23 + 3155945/1811939328*x^22 + 60698495/1811939328*x^21 - 221333255/905969664*x^20 - 54679625/42467328*x^19 + 61144006495/5435817984*x^18 + 805959692135/16307453952*x^17 - 23627873545055/85614133248*x^16 - 92202754097075/57076088832*x^15 + 2564377269108233/1027369598976*x^14 + 14016717238133155/440301256704*x^13 + 8059177780550195/220150628352*x^12 - 1032090099442865177/3852635996160*x^11 - 255383021614939933/275188285440*x^10 - 1319879630259619/9172942848*x^9 + 257419138953129023/53508833280*x^8 + 343337398712800219/34398535680*x^7 + 329057696448850889/120394874880*x^6 - 77266476376935599/4299816960*x^5 - 215564328553850663/7524679680*x^4 - 1037882972607731/69672960*x^3 + 71808945994969/26127360*x^2 + 988411516871/181440*x + 8553103/6
27:
1/134217728*x^27 - 45/67108864*x^26 + 3159/134217728*x^25 - 3185/8388608*x^24 + 258245/134217728*x^23 + 9521655/469762048*x^22 - 661763245/2818572288*x^21 - 60270925/100663296*x^20 + 4798404325/402653184*x^19 + 132327470509/5435817984*x^18 - 9494392741223/25367150592*x^17 - 3772139969191/3170893824*x^16 + 1484019759482027/228304355328*x^15 + 589455699176021/16307453952*x^14 - 250415945707211/10871635968*x^13 - 150351100452672431/285380444160*x^12 - 56183889487802063/57076088832*x^11 + 54350694833907043/23781703680*x^10 + 847310107567473563/71345111040*x^9 + 228419594098511647/17836277760*x^8 - 141343896663787207/5945425920*x^7 - 364955742845955859/4459069440*x^6 - 86878885394938817/1114767360*x^5 + 489404764452839/30965760*x^4 + 354454661873917/3870720*x^3 + 380005230847/5376*x^2 + 148034475/8*x
28:
1/268435456*x^28 - 49/134217728*x^27 + 3801/268435456*x^26 - 35035/134217728*x^25 + 483665/268435456*x^24 + 4304105/402653184*x^23 - 164441329/805306368*x^22 - 22263241/402653184*x^21 + 26707071391/2415919104*x^20 - 10080497063/10871635968*x^19 - 8984671231237/21743271936*x^18 - 5099856153497/10871635968*x^17 + 658631448480689/65229815808*x^16 + 994591701251675/32614907904*x^15 - 23341301381804497/195689447424*x^14 - 122108104539133271/163074539520*x^13 - 68565034338614333/244611809280*x^12 + 96938625562585807/13589544960*x^11 + 1171980497237001829/61152952320*x^10 - 585162297969197/125829120*x^9 - 1699660549979226523/15288238080*x^8 - 2571052349102616353/12740198400*x^7 - 137218691151170729/4777574400*x^6 + 51764291075542489/132710400*x^5 + 6887499125813227/11943936*x^4 + 14177078267471623/49766400*x^3 - 123808606924159/2073600*x^2 - 133246171577173/1252800*x - 23749461029/870
29:
1/536870912*x^29 - 319/1610612736*x^28 + 13601/1610612736*x^27 - 472381/2684354560*x^26 + 12411217/8053063680*x^25 + 6855745/1610612736*x^24 - 264730531/1610612736*x^23 + 1547365963/4831838208*x^22 + 14763738847/1610612736*x^21 - 970368462427/43486543872*x^20 - 50883554918261/130459631616*x^19 + 52066688758879/130459631616*x^18 + 1600161762948287/130459631616*x^17 + 5228758068446641/391378894848*x^16 - 90886975025492851/391378894848*x^15 - 512039704655155057/652298158080*x^14 + 1517359254562987639/978447237120*x^13 + 6642567038745999907/489223618560*x^12 + 2398392605914874543/135895449600*x^11 - 42682015710304034779/611529523200*x^10 - 16930980189568270943/61152952320*x^9 - 4026375753907450463/16986931200*x^8 + 47930935750623964819/76441190400*x^7 + 1405538093353033667/764411904*x^6 + 513510281359061753/318504960*x^5 - 60238334396942669/132710400*x^4 - 11034511862238329/5529600*x^3 - 57086114789377/38400*x^2 - 30535021323/80*x
30:
1/1073741824*x^30 - 115/1073741824*x^29 + 5365/1073741824*x^28 - 125251/1073741824*x^27 + 1333913/1073741824*x^26 + 311025/1073741824*x^25 - 1194537695/9663676416*x^24 + 1732509155/3221225472*x^23 + 65526963775/9663676416*x^22 - 3246137774425/86973087744*x^21 - 27412668787985/86973087744*x^20 + 107721586519655/86973087744*x^19 + 3211408209010345/260919263232*x^18 - 3467958295874975/260919263232*x^17 - 28513955239770205/86973087744*x^16 - 5783755580597623139/11741366845440*x^15 + 876534608478334451/195689447424*x^14 + 2723101105011846533/146767085568*x^13 - 208999555459011863/30576476160*x^12 - 14815727048196555923/73383542784*x^11 - 74232814489811081/169869312*x^10 + 13372048559724564593/45864714240*x^9 + 43755037609407055757/15288238080*x^8 + 212033733867511888169/45864714240*x^7 + 251978613909759829/3822059520*x^6 - 192330079560951796171/20065812480*x^5 - 7400959566028067593/557383680*x^4 - 479338827669299401/76640256*x^3 + 5199005863541263/3548160*x^2 + 894582746652703/374976*x + 8615841276005/14322
Definition
For an integer $k\geq 0$, the Stirling polynomial $S_k(x)$ is the coefficient polynomial in $\mathbb{Q}[x]$ defined by $\left(\frac{t}{1-e^{-t}}\right)^{x+1} =\sum_{k=0}^{\infty}S_k(x)\frac{t^k}{k!}$ [1] [2].
Parameters
$k$
—   index ($k\geq 0$)
Formulas
(1)
$\left(\frac{t}{1-e^{-t}}\right)^{x+1} =\sum_{k=0}^{\infty}S_k(x)\frac{t^k}{k!}$.
(2)
$S_k(x)=B_k^{(x+1)}(x+1)$, where the Noerlund polynomials $B_k^{(a)}(z)$ are defined by $\left(\frac{t}{e^t-1}\right)^a e^{zt} =\sum_{k=0}^{\infty}B_k^{(a)}(z)\frac{t^k}{k!}$ [1]. At $a=1$, these are the Bernoulli polynomials.
(3)
$S_k(-1)=\delta_{k,0}$, $S_k(0)=(-1)^kB_k$, and $S_k(k)=k!$.
(4)
If $m$ and $k$ are integers with $m\geq k\geq0$, then $S_k(m)=\frac{(-1)^k}{\binom{m}{k}}s(m+1,m+1-k)$, where $s(a,b)$ is the signed Stirling number of the first kind [2].
(5)
If $m\geq1$, then $S_k(-m)=\frac{(-1)^k}{\binom{k+m-1}{k}} \left\{ {k+m-1 \atop m-1} \right\}$, where $\left\{ {a \atop b} \right\}$ is the Stirling number of the second kind. These numbers are the coefficients of the Touchard polynomials.
(6)
The shifted sequence is of binomial type: $S_k(x+y-1)=\sum_{j=0}^{k}\binom{k}{j}S_j(x-1)S_{k-j}(y-1)$.
Comments
(7)
This table uses the Sheffer-sequence convention for Stirling polynomials. Knuth's Stirling convolution polynomials $\sigma_n(x)$ and the Gessel-Stanley polynomials $S(n+k,n)$ and $c(n,n-k)$ are different families.
(8)
The Bernoulli numbers in (3) use the convention $B_1=-\tfrac12$.
Programs
(P1)
Sage
import numberdb.sage as numberdb
from sage.arith.misc import factorial
from sage.rings.polynomial.polynomial_ring_constructor import PolynomialRing
from sage.rings.rational_field import QQ

R = PolynomialRing(QQ, 'x')
x = R.gen()

def mul(a, b, order):
    out = [R.zero() for _ in range(order + 1)]
    for i, ai in enumerate(a):
        for j, bj in enumerate(b[:order + 1 - i]):
            out[i + j] += ai * bj
    return out

def base_series(order):
    a = [QQ(0) for _ in range(order + 1)]
    a[0] = QQ(1)
    for r in range(2, order + 2):
        total = QQ(0)
        for m in range(2, r + 1):
            total += a[r - m] * QQ((-1)**(m + 1)) / QQ(factorial(m))
        a[r - 1] = -total
    return a

def binomial_x_plus_1(m):
    value = R.one()
    for j in range(m):
        value *= x + QQ(1 - j)
        value /= QQ(j + 1)
    return value

def stirling_polynomial(k):
    base = [R(c) for c in base_series(k)]
    base[0] = R.zero()
    series = [R.zero() for _ in range(k + 1)]
    series[0] = R.one()
    power = [R.zero() for _ in range(k + 1)]
    power[0] = R.one()
    for m in range(1, k + 1):
        power = mul(power, base, k)
        factor = binomial_x_plus_1(m)
        for j in range(k + 1):
            series[j] += factor * power[j]
    return series[k] * QQ(factorial(k))

stirling_polynomial(31)      # the next one after this table
Links
Similar tables
Bernoulli numbers —   are the values of $(-1)^kS_k(0)$
Bernoulli polynomials —   are the order-one member of the generalized Bernoulli family in (2)
Touchard polynomials —   have Stirling numbers of the second kind as coefficients, which give the negative-integer values in (5)
Data properties
Entries are of type: rational polynomial
Table is complete: no (it holds every index $k$ with $0\leq k\leq30$)
How they were obtained:

The generator computes the ordinary power-series coefficients of $t/(1-e^{-t})$ from the identity $\frac{t}{1-e^{-t}}(1-e^{-t})=t$, then raises that series to the polynomial exponent $x+1$ over Sage's rational polynomial ring. Every division is made in Sage's rational field.

more

Before the draft was created, the entries were checked against interpolation from signed Stirling numbers of the first kind using (4), against (3) and (5), against (6), against the polynomials printed by [1] and [2], and against OEIS A100655 [3] with denominators from A001898 [4].