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.

A121240 Numerator of sum_{k=1..n} 1/2^prime(k).

Table of values

n a(n)
1 1
2 3
3 13
4 53
5 849
6 3397
7 54353
8 217413
9 3478609
10 222630977
11 890523909
12 56993530177
13 911896482833
14 3647585931333
15 58361374901329
16 3735127993685057
17 239048191595843649
18 956192766383374597
19 61196337048535974209

List of values

[1, 3, 13, 53, 849, 3397, 54353, 217413, 3478609, 222630977, 890523909, 56993530177, 911896482833, 3647585931333, 58361374901329, 3735127993685057, 239048191595843649, 956192766383374597, 61196337048535974209]

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

Content is available under The OEIS End-User License Agreement.