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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.

A063103 Numbers k such that sigma(usigma(k)) is prime.

Table of values

n a(n)
1 3
2 8
3 2667
4 3937
5 57337
6 172011
7 253921
8 677207307
9 1073602561
10 732959441001382539
11 750688035198863979
12 1000923107604038521
13 1108158528150703969
14 196751176038481899983340171
15 223076247804911695439842851
16 262302377656070899470360793
17 262336402488441531425882329

List of values

[3, 8, 2667, 3937, 57337, 172011, 253921, 677207307, 1073602561, 732959441001382539, 750688035198863979, 1000923107604038521, 1108158528150703969, 196751176038481899983340171, 223076247804911695439842851, 262302377656070899470360793, 262336402488441531425882329]

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

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