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.

A081295 a(n) = (-1)^(n+1) * coefficient of x^n in Sum_{k>=1} x^k/(1+2*x^k).

Table of values

n a(n)
1 1
2 1
3 5
4 9
5 17
6 29
7 65
8 137
9 261
10 497
11 1025
12 2085
13 4097
14 8129
15 16405
16 32905
17 65537
18 130845
19 262145
20 524793
21 1048645
22 2096129
23 4194305
24 8390821
25 16777233
26 33550337
27 67109125
28 134225865
29 268435457
30 536855053
31 1073741825
32 2147516553
33 4294968325
34 8589869057

List of values

[1, 1, 5, 9, 17, 29, 65, 137, 261, 497, 1025, 2085, 4097, 8129, 16405, 32905, 65537, 130845, 262145, 524793, 1048645, 2096129, 4194305, 8390821, 16777233, 33550337, 67109125, 134225865, 268435457, 536855053, 1073741825, 2147516553, 4294968325, 8589869057]