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 A279280 #6 Feb 16 2025 08:33:37
%S A279280 1,1,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0,0,1,1,0,0,0,0,0,1,1,0,0,0,0,0,0,0,
%T A279280 1,1,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0,0,1,1,0,1,1,0,0,1,1,0,1,1,0,0,0,0,
%U A279280 0,0,0,0,0,1,1,0,0,0,0,0,1,2,1,0,0,0,0,0,1,2,1,0,0,0,0,0,1,1,0,1,1,0,0,0,0,0,1,2,1,0,0,0,1,1,1,2,1,0,0,1,1
%N A279280 Expansion of Product_{k>=1} (1 + x^(k*(5*k-3)/2)).
%C A279280 Number of partitions of n into distinct heptagonal numbers (A000566).
%H A279280 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/HeptagonalNumber.html">Heptagonal Number</a>
%H A279280 <a href="/index/Pol#polygonal_numbers">Index to sequences related to polygonal numbers</a>
%H A279280 <a href="/index/Par#partN">Index entries for related partition-counting sequences</a>
%F A279280 G.f.: Product_{k>=1} (1 + x^(k*(5*k-3)/2)).
%e A279280 a(81) = 2 because we have [81] and [55, 18, 7, 1].
%t A279280 nmax = 120; CoefficientList[Series[Product[1 + x^(k (5 k - 3)/2), {k, 1, nmax}], {x, 0, nmax}], x]
%Y A279280 Cf. A000566, A024940, A033461, A218380, A279012, A279279, A279281.
%K A279280 nonn
%O A279280 0,82
%A A279280 _Ilya Gutkovskiy_, Dec 09 2016