A360218 a(n) is the smallest positive integer which can be represented as the sum of n distinct nonzero square pyramidal numbers in exactly n ways, or -1 if no such integer exists.

1, 5580, 2814, 1980, 1595, 1700, 2175, 2415, 2830, 3740, 4810, 5995, 7610, 9240, 11380, 13896, 16506, 19735, 23150, 27441, 32085, 36721, 42755, 49570, 56610, 65135, 73165, 83021, 93835, 105671, 118255, 132545, 147546, 163516, 182155, 201040, 222371, 244280, 267856

Offset

1,2

Links

Michael S. Branicky, Table of n, a(n) for n = 1..80

Eric Weisstein's World of Mathematics, Square Pyramidal Number

Example

For n = 3: 2814 = 14 + 1015 + 1785 = 55 + 650 + 2109 = 140 + 204 + 2470.

Crossrefs

Cf. A000330, A350206, A350241, A350397, A360217.

Sequence in context: A252907 A300818 A252154 * A065698 A109565 A126784

Adjacent sequences: A360215 A360216 A360217 * A360219 A360220 A360221

Keyword

nonn

Author

Ilya Gutkovskiy, Jan 30 2023

Extensions

a(18)-a(33) from Michael S. Branicky, Feb 04 2023

a(34) and beyond from Michael S. Branicky, Feb 18 2023

Status

approved