A196496 Palindromic centered 37-gonal numbers.

1, 2636362, 106515601, 3066863686603, 148749979947841, 219339595933912, 853637858736358, 6246999091932391909996426, 160549349126909621943945061, 7846331013845693965483101336487, 7874803764137988897314673084787, 1209840308063280743470823608030489021

Offset

1,2

Comments

The centered k-gonal numbers are defined in trottermath.net as (k*n^2-k*n+2)/2, and elsewhere with a slightly different standard index n as (k*n^2+k*n+2)/2. The centered 37-gonal numbers are 1, 38, 112, 223, 371, 556, 778,.... A086272(36,n), where A086272 uses yet another index convention for k. The sequence is generated by centered 37-gonal numbers with standard indices n=1, 377, 2399, 407156,...

Links

Table of n, a(n) for n=1..12.

Patrick De Geest, Palindromic Centered Polygonal Numbers

T. Trotter, Polygonal numbers

Crossrefs

Sequence in context: A233723 A162026 A229799 * A105380 A250911 A157840

Adjacent sequences: A196493 A196494 A196495 * A196497 A196498 A196499

Keyword

nonn,base

Author

Kausthub Gudipati, Oct 03 2011

Extensions

Terms a(8) onward from Patrick De Geest's website added by Max Alekseyev, Oct 28 2025

Status

approved