History of Wilbraham-Gibbs constant

+Title: Wilbraham-Gibbs constant+Definition: The Wilbraham-Gibbs constant $G'$ is defined as $G' = \text{Si}(\pi) =+  \int_0^\pi \frac{\sin t}{t} dt$. The Gibbs constant $G$ is defined as $G'/(\pi/2)$.+Parameters:+  expression:+    title: Transformation of constant+    type: Symbolic+    show-in-parameter-list: 'no'+Comments:+  comment-Gibbs-phenomenon: If $f$ is a periodic piecewise continuously differentiable+    function  with a jump of a certain size at a discontinuity of $f$, then for large+    $n$,  the $n$'th partial Fourier expansion of $f$ will overshoot this jump by+    a factor of approximately $(G-1)/2$ at each side, and by a factor of $(G-1)$ in+    total. This is known as the Gibbs phenomenon CITE{Wiki}.+Formulas: {}+Programs: {}+References:+  Fin:+    bib: Finch, S. R., "Gibbs-Wilbraham Constant."  §4.1 in "Mathematical Constants".  Cambridge+      University Press, pp. 248-250, (2003).+  Wil:+    bib: 'Wilbraham, Henry, "On a certain periodic function",  The Cambridge and Dublin+      Mathematical Journal, 3: 198–201, (1848).'+Links:+  MathWorld:+    title: 'MathWorld: Wilbraham-Gibbs Constant'+    url: https://mathworld.wolfram.com/Wilbraham-GibbsConstant.html+  OEIS_A243268:+    title: 'OEIS: A243268'+    url: https://oeis.org/A243268+  OEIS_A036792:+    title: 'OEIS: A036792'+    url: https://oeis.org/A036792+  Wiki:+    title: 'Wikipedia: Gibbs phenomenon'+    url: https://en.wikipedia.org/wiki/Gibbs_phenomenon+Similar tables: ''+Keywords: ''+Tags:+- analysis+- Fourier series+Data properties:+  type: R+Display properties: ''+Numbers:+  WG:+    param-latex: $G'$+    number: '1.851937051982466170361053370157991363345809728981154909804783781876981890166348358532710336502954757'+  G:+    param-latex: $G$+    number: '1.178979744472167270232028845824909741463897420964366146834503705768303703705043859077668347949410421'+  G-1:+    param-latex: $G-1$+    number: '0.178979744472167270232028845824909741463897420964366146834503705768303703705043859077668347949410421'+  (G-1)/2:+    param-latex: $(G-1)/2$+    number: '0.089489872236083635116014422912454870731948710482183073417251852884151851852521929538834173974705210'