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.

A331864 Numbers k such that R(k) + 2*10^floor(k/2-1) is prime, where R(k) = (10^k-1)/9 (repunit: A002275).

Table of values

n a(n)
1 2
2 3
3 5
4 8
5 9
6 39
7 78
8 81
9 155
10 249
11 387
12 395
13 510
14 711
15 1173
16 1751
17 10245

List of values

[2, 3, 5, 8, 9, 39, 78, 81, 155, 249, 387, 395, 510, 711, 1173, 1751, 10245]

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

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