%I #6 Nov 07 2017 03:37:14
%S 1,1,1,1,2,2,2,3,4,4,4,5,6,7,8,9,10,11,13,14,16,18,20,21,23,26,29,32,
%T 35,38,41,45,49,53,59,64,69,73,80,87,94,101,109,117,125,134,145,156,
%U 167,178,190,202,217,232,249,265,282,299,318,339,361,384,408,432,457,484,514,545,578,610,646
%N Number of partitions of n into generalized heptagonal numbers (A085787).
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/HeptagonalNumber.html">Heptagonal Number</a>
%H <a href="/index/Pol#polygonal_numbers">Index to sequences related to polygonal numbers</a>
%H <a href="/index/Par#part">Index entries for related partition-counting sequences</a>
%F G.f.: Product_{k>=1} 1/((1 - x^(k*(5*k-3)/2))*(1 - x^(k*(5*k+3)/2))).
%e a(8) = 4 because we have [7, 1], [4, 4], [4, 1, 1, 1, 1] and [1, 1, 1, 1, 1, 1, 1, 1].
%t nmax = 70; CoefficientList[Series[Product[1/((1 - x^(k (5 k - 3)/2)) (1 - x^(k (5 k + 3)/2))), {k, 1, nmax}], {x, 0, nmax}], x]
%Y Cf. A007294, A085787, A095699, A279012, A294622, A294623.
%K nonn
%O 0,5
%A _Ilya Gutkovskiy_, Nov 05 2017