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 A029830 #23 Feb 27 2018 07:51:46
%S A029830 174611,13200,6920614800,15341851377600,3628395292275600,
%T A029830 251770019531263200,8043563916910526400,150465416446925500800,
%U A029830 1902324110996589786000,17831242688625346952400,132000251770026451864800,807299993919072011054400,4217144038884527916580800,19297347832955888660949600
%N A029830 Eisenstein series E_20(q) (alternate convention E_10(q)), multiplied by 174611.
%D A029830 J.-P. Serre, Course in Arithmetic, Chap. VII, Section 4.
%H A029830 Seiichi Manyama, <a href="/A029830/b029830.txt">Table of n, a(n) for n = 0..10000</a>
%H A029830 <a href="/index/Ed#Eisen">Index entries for sequences related to Eisenstein series</a>
%F A029830 a(n) = 53361*A282015(n) + 121250*A282292(n). - _Seiichi Manyama_, Feb 11 2017
%t A029830 terms = 14;
%t A029830 E20[x_] = 174611 + 13200*Sum[k^19*x^k/(1 - x^k), {k, 1, terms}];
%t A029830 E20[x] + O[x]^terms // CoefficientList[#, x]& (* _Jean-François Alcover_, Feb 27 2018 *)
%o A029830 (PARI) a(n)=if(n<1,174611*(n==0),13200*sigma(n,19))
%Y A029830 Cf. A006352 (E_2), A004009 (E_4), A013973 (E_6), A008410 (E_8), A013974 (E_10), A029828 (691*E_12), A058550 (E_14), A029829 (3617*E_16), A279892 (43867*E_18), this sequence (174611*E_20), A279893 (77683*E_22), A029831 (236364091*E_24).
%Y A029830 Cf. A282015 (E_4^5), A282292 (E_4^2*E_6^2 = E_10^2).
%K A029830 nonn,easy
%O A029830 0,1
%A A029830 _N. J. A. Sloane_