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.

A254627 Indices of centered pentagonal numbers (A005891) that are also triangular numbers (A000217).

Table of values

n a(n)
1 1
2 2
3 11
4 28
5 189
6 494
7 3383
8 8856
9 60697
10 158906
11 1089155
12 2851444
13 19544085
14 51167078
15 350704367
16 918155952
17 6293134513
18 16475640050
19 112925716859
20 295643364940
21 2026369768941
22 5305104928862
23 36361730124071
24 95196245354568
25 652484772464329

List of values

[1, 2, 11, 28, 189, 494, 3383, 8856, 60697, 158906, 1089155, 2851444, 19544085, 51167078, 350704367, 918155952, 6293134513, 16475640050, 112925716859, 295643364940, 2026369768941, 5305104928862, 36361730124071, 95196245354568, 652484772464329]