A336693 Period of binary representation of 1/(1+sigma(n)).

1, 1, 4, 1, 3, 12, 6, 1, 3, 18, 12, 28, 4, 20, 20, 1, 18, 4, 6, 14, 10, 36, 20, 60, 1, 14, 20, 18, 5, 9, 10, 1, 21, 20, 21, 11, 12, 60, 18, 12, 14, 48, 12, 8, 39, 9, 21, 100, 28, 23, 9, 30, 20, 110, 9, 110, 54, 12, 60, 156, 6, 48, 12, 1, 8, 28, 22, 7, 48, 28, 9, 21, 20, 44, 100, 46, 48, 156, 54, 40, 60, 7, 8, 60

Offset: 1

Author

Antti Karttunen, Jul 31 2020

Keywords

• nonn

Links

• Antti Karttunen, Table of n, a(n) for n = 1..16384
• Antti Karttunen, Data supplement: n, a(n) computed for n = 1..65537
• Index entries for sequences related to sigma(n)

Crossrefs

Cf. A000203, A007733, A088580, A324294, A332459, A336691, A336692, A336694, A336695.

Programs

PARI

A007733(n) = znorder(Mod(2, n/2^valuation(n, 2))); \\ From A007733
A336693(n) = A007733(1+sigma(n));

Formula

a(n) = A007733(1+A000203(n)) = A007733(A088580(n)) = A007733(A332459(n)).