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 A145621 #17 Jun 05 2016 23:33:43
%S A145621 105,31087,2538991,248821433,21946050833,11828921402977,
%T A145621 7535022933740305,3692161237533130831,1025190103621701235981,
%U A145621 954451986471803883166747,15589382445706130101521201
%N A145621 Numerator of the polynomial A_l(x) = sum_{d=1..l-1} x^(l-d)/d for index l=2n+1 evaluated at x=7.
%C A145621 For denominators see A145622. For general properties of A_l(x) see A145609.
%H A145621 Robert Israel, <a href="/A145621/b145621.txt">Table of n, a(n) for n = 1..390</a>
%p A145621 f:= n -> numer(add(7^(2*n+1-d)/d, d=1..2*n)):
%p A145621 map(f, [$1..40]); # _Robert Israel_, Jun 05 2016
%t A145621 m = 7; aa = {}; Do[k = 0; Do[k = k + m^(2 r + 1 - d)/d, {d, 1, 2 r}]; AppendTo[aa, Numerator[k]], {r, 1, 25}]; aa (* _Artur Jasinski_ *)
%t A145621 a[n_,m_]:=Integrate[(m-x^n)/(m-x),{x,0,1}]+(m^n-m)Log[m/(m-1)]
%t A145621 Table[7 a[2 n, 7] // FullSimplify // Numerator, {n,1,25}] (* _Gerry Martens_ , Jun 04 2016 *)
%Y A145621 Cf. A145609 - A145640.
%K A145621 frac,nonn
%O A145621 1,1
%A A145621 _Artur Jasinski_, Oct 14 2008
%E A145621 Edited by _R. J. Mathar_, Aug 21 2009