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.

A274962 Numbers n such that sigma(n) and sigma(n) + 2 are both primes.

Table of values

n a(n)
1 2
2 2401
3 19356878641
4 46904541018721
5 119601542190001
6 360371335935601
7 16472757578830081
8 26835157974988801
9 59879777952495601
10 147669280778756881
11 170589096345900241
12 219660193449998401
13 1103765757989399761
14 1515946818108402241
15 2044393722679974961
16 2608728003079029841
17 2805689752523610241
18 3071293995460971361
19 4537323492222149281
20 9583348094642219041
21 9982134924573725761

List of values

[2, 2401, 19356878641, 46904541018721, 119601542190001, 360371335935601, 16472757578830081, 26835157974988801, 59879777952495601, 147669280778756881, 170589096345900241, 219660193449998401, 1103765757989399761, 1515946818108402241, 2044393722679974961, 2608728003079029841, 2805689752523610241, 3071293995460971361, 4537323492222149281, 9583348094642219041, 9982134924573725761]

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

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