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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.

A309128 (1/n) times the sum of the elements of all subsets of [n] whose sum is divisible by n.

Table of values

n a(n)
1 1
2 1
3 4
4 4
5 12
6 20
7 40
8 70
9 150
10 284
11 564
12 1116
13 2212
14 4392
15 8768
16 17404
17 34704
18 69214
19 137980
20 275264
21 549340
22 1096244
23 2188344
24 4369196
25 8724196
26 17422500
27 34797476
28 69505628
29 138845940
30 277383904
31 554189344
32 1107296248
33 2212559996
34 4421289872
35 8835361488

List of values

[1, 1, 4, 4, 12, 20, 40, 70, 150, 284, 564, 1116, 2212, 4392, 8768, 17404, 34704, 69214, 137980, 275264, 549340, 1096244, 2188344, 4369196, 8724196, 17422500, 34797476, 69505628, 138845940, 277383904, 554189344, 1107296248, 2212559996, 4421289872, 8835361488]

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

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