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 A222028 #15 May 13 2013 01:24:11
%S A222028 2,4,8,15,28,41,66,92,132,175,232,287,360,475,570,727,852,1009,1220,
%T A222028 1397,1646,1891,2154,2441,2772,3121,3508,3891,4334,4791,5282,5797,
%U A222028 6376,6983,7618,8285,8984,9713,10500,11319,12182,13093,14028,15023,16064,17157,18276,19447,20680,21953
%N A222028 a(n) is the number of terms in the expansion of (x-y)(x^3-y^3)*(x^6-y^6)*(x^10-y^10)*...*(x^T_i-y^T_i), where T_i is the i-th triangular number.
%C A222028 In the definition one can take y=1. Thus the sequence becomes the number of terms in the polynomial of the product{k=0..n} (1-x^T_i), where G_i is the i-th triangular number.
%t A222028 f[n_] := Length@ ExpandAll@ Product[1 - x^(k (k + 1)/2), {k, n}]; Array[f, 50]
%Y A222028 Cf. A000124, A086781, A086795, A086796, A086817, A221991, A225549.
%K A222028 nonn
%O A222028 1,1
%A A222028 _Robert G. Wilson v_, May 12 2013