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.

A138503 a(n) = Sum_{d|n} (-1)^(d-1)*d^3.

Table of values

n a(n)
1 1
2 -7
3 28
4 -71
5 126
6 -196
7 344
8 -583
9 757
10 -882
11 1332
12 -1988
13 2198
14 -2408
15 3528
16 -4679
17 4914
18 -5299
19 6860
20 -8946
21 9632
22 -9324
23 12168
24 -16324
25 15751
26 -15386
27 20440
28 -24424
29 24390
30 -24696
31 29792
32 -37447
33 37296
34 -34398
35 43344
36 -53747
37 50654
38 -48020
39 61544
40 -73458

List of values

[1, -7, 28, -71, 126, -196, 344, -583, 757, -882, 1332, -1988, 2198, -2408, 3528, -4679, 4914, -5299, 6860, -8946, 9632, -9324, 12168, -16324, 15751, -15386, 20440, -24424, 24390, -24696, 29792, -37447, 37296, -34398, 43344, -53747, 50654, -48020, 61544, -73458]