A319185 Numbers that are sums of consecutive hexagonal numbers (A000384).

0, 1, 6, 7, 15, 21, 22, 28, 43, 45, 49, 50, 66, 73, 88, 91, 94, 95, 111, 120, 139, 153, 154, 157, 160, 161, 190, 202, 211, 230, 231, 245, 251, 252, 273, 276, 277, 322, 325, 343, 350, 364, 365, 371, 372, 378, 421, 430, 435, 463, 475, 496, 503, 507, 518, 524, 525, 554, 561

Offset

1,3

Links

Table of n, a(n) for n=1..59.

Eric Weisstein's World of Mathematics, Hexagonal Number

Mathematica

anmax = 1000; nmax = Floor[Sqrt[anmax/2]] + 1; Select[Union[Flatten[Table[Sum[k*(2*k-1), {k, i, j}], {i, 0, nmax}, {j, i, nmax}]]], # <= anmax &] (* Vaclav Kotesovec, Dec 21 2018 *)

Crossrefs

Cf. A000384, A002412, A034705, A034706, A319184, A322636, A322637.

Sequence in context: A085512 A165767 A292348 * A196223 A106680 A214325

Adjacent sequences: A319182 A319183 A319184 * A319186 A319187 A319188

Keyword

nonn

Author

Ilya Gutkovskiy, Dec 21 2018

Status

approved