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.

A216392 Number of values of k for which sigma(k) is a permutation of decimal digits of k, for k < 2^n.

Table of values

n a(n)
1 1
2 1
3 1
4 1
5 1
6 1
7 2
8 2
9 5
10 7
11 7
12 13
13 16
14 21
15 35
16 57
17 83
18 143
19 207
20 278
21 457
22 790
23 1064
24 1815
25 3468
26 5194
27 8226

List of values

[1, 1, 1, 1, 1, 1, 2, 2, 5, 7, 7, 13, 16, 21, 35, 57, 83, 143, 207, 278, 457, 790, 1064, 1815, 3468, 5194, 8226]