A360836 a(n) is the least n-gonal pyramidal number that is the sum of two or more consecutive nonzero n-gonal pyramidal numbers in more than one way.

12880, 18896570

Offset

2,1

Comments

a(4) > 10^19 if it exists. - Michael S. Branicky, Feb 23 2023

Links

Table of n, a(n) for n=2..3.

Eric Weisstein's World of Mathematics, Pyramidal Number

Example

For n = 2: 12880 = 91 + ... + 903 = 300 + ... + 990.
For n = 3: 18896570 = 708561 + ... + 1021384 = 2604125 + ... + 2796160.

Crossrefs

Cf. A080851, A360762.

Sequence in context: A251922 A184453 A233936 * A158918 A185885 A212079

Adjacent sequences: A360833 A360834 A360835 * A360837 A360838 A360839

Keyword

nonn,bref,more

Author

Ilya Gutkovskiy, Feb 23 2023

Status

approved