A337195 The 2-adic valuation of 1+A000265(sigma(n)), where A000265 gives the odd part.

1, 2, 1, 3, 2, 2, 1, 4, 1, 1, 2, 3, 3, 2, 2, 5, 1, 3, 1, 1, 1, 1, 2, 4, 5, 1, 1, 3, 4, 1, 1, 6, 2, 2, 2, 2, 2, 4, 3, 1, 1, 2, 2, 1, 3, 1, 2, 5, 1, 1, 1, 1, 2, 4, 1, 4, 1, 1, 4, 1, 5, 2, 1, 7, 1, 1, 1, 6, 2, 1, 1, 2, 1, 1, 5, 2, 2, 1, 1, 1, 1, 6, 1, 3, 2, 1, 4, 1, 1, 1, 3, 1, 1, 1, 4, 6, 1, 2, 3, 1, 2, 2, 1, 1, 2

Offset: 1

Author

Antti Karttunen, Aug 18 2020

Keywords

• nonn

Links

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

Crossrefs

Cf. A000203, A000265, A007814, A161942, A336698, A337194, A337196.

Programs

PARI

A007814(n) = valuation(n,2);
A000265(n) = (n>>A007814(n));
A337195(n) = A007814(1+A000265(sigma(n)));

Formula

a(n) = A007814(A337194(n)) = A007814(1+A000265(A000203(n))).