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.

A253470 Indices of centered triangular numbers (A005448) which are also centered pentagonal numbers (A005891).

Table of values

n a(n)
1 1
2 5
3 36
4 280
5 2201
6 17325
7 136396
8 1073840
9 8454321
10 66560725
11 524031476
12 4125691080
13 32481497161
14 255726286205
15 2013328792476
16 15850904053600
17 124793903636321
18 982500325036965
19 7735208696659396
20 60899169248238200
21 479458145289246201
22 3774765993065731405

List of values

[1, 5, 36, 280, 2201, 17325, 136396, 1073840, 8454321, 66560725, 524031476, 4125691080, 32481497161, 255726286205, 2013328792476, 15850904053600, 124793903636321, 982500325036965, 7735208696659396, 60899169248238200, 479458145289246201, 3774765993065731405]

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

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