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%I #10 Apr 14 2020 12:34:31
%S 1,872,8240232,263346158075
%N a(n) is the least integer that can be expressed as the sum of one or more consecutive nonzero heptagonal numbers in exactly n ways.
%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>
%e Let S(k, m) denote the sum of m heptagonal numbers starting from the k-th. We have
%e a(1) = S(1, 1);
%e a(2) = S(13, 2) = S(3, 8);
%e a(3) = S(133, 98) = S(479, 14) = S(168, 77);
%e a(4) = S(6773, 1785) = S(810, 6006) = S(7467, 1547) = S(38758, 70).
%Y Cf. A000566, A054859, A068314, A186337, A298467, A322636, A334007, A334008, A334010, A334012.
%K nonn,hard,more
%O 1,2
%A _Ilya Gutkovskiy_, Apr 12 2020
%E a(4) from _Giovanni Resta_, Apr 14 2020
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