A360217 a(n) is the smallest positive integer which can be represented as the sum of n distinct nonzero tetrahedral numbers in exactly n ways, or -1 if no such integer exists.

1, 140, 305, 315, 435, 644, 830, 1141, 1425, 1925, 2380, 3010, 3805, 4720, 5806, 7095, 8510, 10200, 12020, 14115, 16460, 19131, 21990, 25425, 29275, 33495, 37425, 42680, 48300, 54545, 60711, 68391, 75726, 84815, 93370, 103250, 114115, 125360, 137831, 150995, 165545, 179830

Offset

1,2

Links

Table of n, a(n) for n=1..42.

Eric Weisstein's World of Mathematics, Tetrahedral Number

Example

For n = 3: 305 = 1 + 84 + 220 = 20 + 120 + 165 = 56 + 84 + 165.

Crossrefs

Cf. A000292, A350205, A350288, A350397, A360218.

Sequence in context: A140798 A325022 A337689 * A249554 A196447 A255783

Adjacent sequences: A360214 A360215 A360216 * A360218 A360219 A360220

Keyword

nonn

Author

Ilya Gutkovskiy, Jan 30 2023

Extensions

More terms from David A. Corneth, Jan 30 2023

Status

approved