cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A253458 Indices of centered heptagonal numbers (A069099) which are also centered hexagonal numbers (A003215).

Table of values

n a(n)
1 1
2 13
3 325
4 8425
5 218713
6 5678101
7 147411901
8 3827031313
9 99355402225
10 2579413426525
11 66965393687413
12 1738520822446201
13 45134575989913801
14 1171760454915312613
15 30420637251808214125
16 789764808092098254625
17 20503464373142746406113
18 532300308893619308304301

List of values

[1, 13, 325, 8425, 218713, 5678101, 147411901, 3827031313, 99355402225, 2579413426525, 66965393687413, 1738520822446201, 45134575989913801, 1171760454915312613, 30420637251808214125, 789764808092098254625, 20503464373142746406113, 532300308893619308304301]