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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.

A232108 a(n) = [x^(n*(n+1)/2)] G(x)^(n+1) where G(x) = Sum_{n>=0} x^(n*(n+1)/2).

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%I A232108 #9 Nov 19 2013 04:00:49
%S A232108 1,2,4,14,90,438,3151,24390,204156,1833212,17301306,175936764,
%T A232108 1870247133,20872753540,243478609605,2957875659062,37319273049382,
%U A232108 487266892836348,6574891059415183,91475580555526776,1309960647920094337,19278546942842385994,291167370195970990704,4507447478297070537800
%N A232108 a(n) = [x^(n*(n+1)/2)] G(x)^(n+1) where G(x) = Sum_{n>=0} x^(n*(n+1)/2).
%H A232108 Paul D. Hanna, <a href="/A232108/b232108.txt">Table of n, a(n) for n = 0..100</a>
%e A232108 Let G(x) = 1 + x + x^3 + x^6 + x^10 + x^15 + x^21 + x^28 + x^36 +...
%e A232108 then a(n) = the coefficient of x^(n*(n+1)/2) in G(x)^n.
%e A232108 Coefficients of x^k in powers of G(x)^n begin:
%e A232108 n\k...0...1..2..3..4..5...6...7...8...9..10..11..12...13..14...15...16...
%e A232108 n=1: [(1),1, 0, 1, 0, 0,  1,  0,  0,  0,  1,  0,  0,   0,  0,   1,   0,...];
%e A232108 n=2: [1, (2),1, 2, 2, 0,  3,  2,  0,  2,  2,  2,  1,   2,  0,   2,   4,...];
%e A232108 n=3: [1,  3, 3,(4),6, 3,  6,  9,  3,  7,  9,  6,  9,   9,  6,   6,  15,...];
%e A232108 n=4: [1,  4, 6, 8,13,12,(14),24, 18, 20, 32, 24, 31,  40, 30,  32,  48,...];
%e A232108 n=5: [1,  5,10,15,25,31, 35, 55, 60, 60,(90),90, 95, 135,125, 126, 170,...];
%e A232108 n=6: [1,  6,15,26,45,66, 82,120,156,170,231,276,290, 390,435,(438),561,...]; ...
%e A232108 the coefficients in parenthesis form the initial terms of this sequence.
%o A232108 (PARI) {a(n)=local(G=sum(m=0, n+1, x^(m*(m+1)/2))+x*O(x^(n*(n+1)/2))); polcoeff(G^(n+1), n*(n+1)/2)}
%o A232108 for(n=0,30,print1(a(n),", "))
%Y A232108 Cf. A196010.
%K A232108 nonn
%O A232108 0,2
%A A232108 _Paul D. Hanna_, Nov 18 2013