A112759 Total number of prime factors of n-th 5-smooth number.

0, 1, 1, 2, 1, 2, 3, 2, 2, 3, 2, 4, 3, 3, 4, 2, 3, 3, 5, 4, 4, 3, 5, 3, 4, 4, 6, 5, 3, 5, 4, 4, 6, 4, 5, 5, 3, 7, 4, 6, 4, 6, 5, 5, 7, 5, 6, 4, 6, 5, 4, 8, 5, 7, 5, 7, 6, 6, 4, 8, 6, 5, 7, 5, 7, 6, 5, 9, 6, 8, 6, 4, 8, 7, 5, 7, 6, 5, 9, 7, 6, 8, 6, 8, 7, 6, 10, 7, 5, 9, 7, 6, 5, 9, 8, 6, 8, 7, 6, 10, 8, 7, 9, 7

Offset

1,4

Links

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

Formula

a(n) = A001222(A051037(n));

a(n) = A112760(n) + A112761(n) + A112762(n).

Mathematica

PrimeOmega @ Select[Range[3000], Last @ Map[First, FactorInteger[#]] <= 5 &] (* Amiram Eldar, Feb 07 2020 *)

Crossrefs

Cf. A001222, A051037, A069352, A112754, A112758, A112760, A112761, A112762.

Sequence in context: A239507 A216448 A216763 * A309971 A096862 A029309

Adjacent sequences: A112756 A112757 A112758 * A112760 A112761 A112762

Keyword

nonn

Author

Reinhard Zumkeller, Sep 18 2005

Status

approved