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.

A339916 The sum of 2^((d-1)/2) over all divisors of 2n+1.

Table of values

n a(n)
0 1
1 3
2 5
3 9
4 19
5 33
6 65
7 135
8 257
9 513
10 1035
11 2049
12 4101
13 8211
14 16385
15 32769
16 65571
17 131085
18 262145
19 524355
20 1048577
21 2097153
22 4194455
23 8388609
24 16777225
25 33554691
26 67108865
27 134217765
28 268435971
29 536870913
30 1073741825
31 2147484699
32 4294967365
33 8589934593
34 17179871235
35 34359738369
36 68719476737

List of values

[1, 3, 5, 9, 19, 33, 65, 135, 257, 513, 1035, 2049, 4101, 8211, 16385, 32769, 65571, 131085, 262145, 524355, 1048577, 2097153, 4194455, 8388609, 16777225, 33554691, 67108865, 134217765, 268435971, 536870913, 1073741825, 2147484699, 4294967365, 8589934593, 17179871235, 34359738369, 68719476737]