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 A156180 #9 Jul 02 2020 10:45:11 %S A156180 1,6,9,108,81,486,729,17496,6561,39366,59049,708588,531441,3188646, %T A156180 4782969,229582512,43046721,258280326,387420489,4649045868,3486784401, %U A156180 20920706406,31381059609,753145430616,282429536481,1694577218886,2541865828329,30502389939948 %N A156180 Denominator of Euler(n,1/3). %H A156180 Michael E. Hoffman, <a href="https://doi.org/10.37236/1453">Derivative Polynomials, Euler Polynomials, and Associated Integer Sequences</a>, The Electronic Journal of Combinatorics, Volume 6.1 (1999): Research paper R21, 13 p. See Eq. (14). %e A156180 1, -1/6, -2/9, 13/108, 22/81, -121/486, -602/729, 18581/17496, ... %p A156180 [seq(euler(n,1/3),n=0..50)]; %t A156180 Denominator[EulerE[Range[0,30],1/3]] (* _Harvey P. Dale_, Aug 14 2011 *) %Y A156180 Cf. A156179. %K A156180 nonn %O A156180 0,2 %A A156180 _N. J. A. Sloane_, Nov 07 2009