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.

A099442 Semiprimes of the form 2^k-k-1.

Table of values

n a(n)
1 4
2 26
3 57
4 247
5 502
6 4083
7 1073741793
8 4294967263
9 8589934558
10 70368744177617
11 4503599627370443
12 4611686018427387841
13 18889465931478580854709
14 75557863725914323419059
15 77371252455336267181195177
16 316912650057057350374175801245

List of values

[4, 26, 57, 247, 502, 4083, 1073741793, 4294967263, 8589934558, 70368744177617, 4503599627370443, 4611686018427387841, 18889465931478580854709, 75557863725914323419059, 77371252455336267181195177, 316912650057057350374175801245]

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

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