A246456 a(n) = sigma(n + sigma(n)).

3, 6, 8, 12, 12, 39, 24, 24, 36, 56, 24, 90, 40, 60, 56, 48, 48, 80, 56, 96, 54, 90, 48, 224, 120, 126, 68, 224, 60, 216, 104, 120, 121, 180, 84, 128, 124, 171, 120, 252, 84, 288, 120, 255, 168, 180, 120, 308, 162, 168, 168, 372, 108, 360, 128, 372, 138, 266

Offset

1,1

Links

Table of n, a(n) for n=1..58.

Example

For n = 6; a(n) = sigma(6 + sigma(6)) = sigma(18) = 39.

Prog

(Magma) [SumOfDivisors(n+SumOfDivisors(n)):n in[1..1000]]
(PARI)
vector(100, n, sigma(n+sigma(n))) \\ Derek Orr, Sep 07 2014

Crossrefs

Cf. A000203, A246909, A246907 (numbers n such that a(n) = 3n), A246915 (numbers n such that a(n) = a(n+1)).

Cf. Sequences of numbers n such that a(n) = k*sigma(n):

A246857 (k=2), A246910 (k=3), A246911 (k=4), A246912 (k=5), A246913 (k=6).

Sequence in context: A080598 A233541 A077148 * A070528 A243117 A356180

Adjacent sequences: A246453 A246454 A246455 * A246457 A246458 A246459

Keyword

nonn

Author

Jaroslav Krizek, Sep 07 2014

Status

approved