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 A157864 #4 Feb 13 2013 20:18:39 %S A157864 1,17,72,2431,5112,85697,357912,23835887,24721272,408926687, %T A157864 1685915352,55444767181,113654162232,1859089273877,7584695511192, %U A157864 988081196223199,501829640287992,8141400285401267,32967597006585432,1066454822660748331,2153382250687098552 %N A157864 Numerator of Euler(n,9). %t A157864 Numerator[EulerE[Range[0,20],9]] (* _Harvey P. Dale_, Feb 13 2013 *) %Y A157864 For denominators see A006519. %K A157864 nonn,frac %O A157864 0,2 %A A157864 _N. J. A. Sloane_, Nov 10 2009