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.

A253879 Indices of centered heptagonal numbers (A069099) which are also triangular numbers (A000217).

Table of values

n a(n)
1 1
2 9
3 136
4 2160
5 34417
6 548505
7 8741656
8 139317984
9 2220346081
10 35386219305
11 563959162792
12 8987960385360
13 143243407002961
14 2282906551662009
15 36383261419589176
16 579849276161764800
17 9241205157168647617
18 147279433238536597065
19 2347229726659416905416

List of values

[1, 9, 136, 2160, 34417, 548505, 8741656, 139317984, 2220346081, 35386219305, 563959162792, 8987960385360, 143243407002961, 2282906551662009, 36383261419589176, 579849276161764800, 9241205157168647617, 147279433238536597065, 2347229726659416905416]

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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