A334011 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.

1, 872, 8240232, 263346158075

Offset: 1

Author

Ilya Gutkovskiy, Apr 12 2020

Keywords

• nonn
• hard
• more

Examples

			Let S(k, m) denote the sum of m heptagonal numbers starting from the k-th. We have
a(1) = S(1, 1);
a(2) = S(13, 2) = S(3, 8);
a(3) = S(133, 98) = S(479, 14) = S(168, 77);
a(4) = S(6773, 1785) = S(810, 6006) = S(7467, 1547) = S(38758, 70).
		

Links

• Eric Weisstein's World of Mathematics, Heptagonal Number
• Index to sequences related to polygonal numbers

Crossrefs

Cf. A000566, A054859, A068314, A186337, A298467, A322636, A334007, A334008, A334010, A334012.

Extensions

a(4) from Giovanni Resta, Apr 14 2020