A099550 Odd part of n modulo 9.

1, 1, 3, 1, 5, 3, 7, 1, 0, 5, 2, 3, 4, 7, 6, 1, 8, 0, 1, 5, 3, 2, 5, 3, 7, 4, 0, 7, 2, 6, 4, 1, 6, 8, 8, 0, 1, 1, 3, 5, 5, 3, 7, 2, 0, 5, 2, 3, 4, 7, 6, 4, 8, 0, 1, 7, 3, 2, 5, 6, 7, 4, 0, 1, 2, 6, 4, 8, 6, 8, 8, 0, 1, 1, 3, 1, 5, 3, 7, 5, 0, 5, 2, 3, 4, 7, 6, 2, 8, 0, 1, 5, 3, 2, 5, 3, 7, 4, 0, 7, 2, 6

Offset: 1

Author

Ralf Stephan, Oct 23 2004

Keywords

• nonn
• easy

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A000265, A010878.

Cf. A099544, A099545, A099546, A099547, A099548, A099549, A099551.

Programs

Mathematica

a[n_] := Mod[n / 2^IntegerExponent[n, 2], 9]; Array[a, 100] (* Amiram Eldar, Aug 29 2024 *)

PARI

a(n) = (n>>valuation(n, 2))%9 \\Charles R Greathouse IV, May 14 2014

Formula

a(n) = A010878(A000265(n)).

Asymptotic mean: Limit_{m->oo} (1/m) * Sum_{k=1..m} a(k) = 4. - Amiram Eldar, Aug 29 2024