This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A059342 #14 Jul 02 2025 16:02:00
%S A059342 1,1,2,1,1,1,1,2,1,4,1,1,1,1,1,1,2,1,2,1,2,1,1,1,1,1,1,1,1,2,1,4,1,2,
%T A059342 1,8,1,1,1,1,1,1,1,1,1,1,2,1,1,1,1,1,2,1,2,1,1,1,1,1,1,1,1,1,1,1,1,2,
%U A059342 1,4,1,1,1,4,1,2,1,4,1,1,1,1,1,1,1,1,1,1,1,1,1,1,2,1,2,1,2,1,2,1,2,1,2,1,2
%N A059342 Triangle giving denominators of coefficients of Euler polynomials, highest powers first.
%D A059342 M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, 1964 (and various reprintings), p. 809.
%D A059342 L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 48, [14b].
%H A059342 G. C. Greubel, <a href="/A059342/b059342.txt">Table of n, a(n) for the first 50 rows, flattened</a>
%H A059342 M. Abramowitz and I. A. Stegun, eds., <a href="http://www.convertit.com/Go/ConvertIt/Reference/AMS55.ASP">Handbook of Mathematical Functions</a>, National Bureau of Standards, Applied Math. Series 55, Tenth Printing, 1972 [alternative scanned copy].
%e A059342 1; x-1/2; x^2-x; x^3-3*x^2/2+1/4; ...
%p A059342 for n from 0 to 30 do for k from n to 0 by -1 do printf(`%d,`,denom(coeff(euler(n,x), x, k))) od:od:
%t A059342 Denominator[Table[Reverse[CoefficientList[Series[EulerE[n, x], {x, 0, 20}], x]], {n, 0, 10}]] (* _G. C. Greubel_, Jan 07 2017 *)
%Y A059342 Cf. A059341. See also A004172 A004173 A004174 A004175 A011934 A020523 A020524 A020525 A020526 A020547 A020548 A058940.
%K A059342 nonn,tabf,frac,easy
%O A059342 0,3
%A A059342 _N. J. A. Sloane_, Jan 27 2001
%E A059342 More terms from _James Sellers_, Jan 29 2001