A112762 Exponent of 5 (value of k) in n-th number of the form 2^i*3^j*5^k.

0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 1, 0, 2, 0, 1, 0, 0, 1, 1, 0, 2, 0, 1, 0, 0, 2, 1, 0, 1, 0, 2, 0, 1, 3, 0, 1, 0, 2, 1, 0, 1, 0, 2, 0, 2, 1, 0, 3, 0, 1, 0, 2, 1, 0, 1, 3, 0, 2, 1, 0, 2, 1, 0, 3, 0, 1, 0, 2, 4, 1, 0, 2, 1, 0, 3, 0, 2, 1, 0, 2, 1, 0, 3, 0, 1, 3, 0, 2, 1, 4, 1, 0, 2, 1, 0, 3, 0, 2, 1, 0, 2, 4

Offset: 1

Author

Reinhard Zumkeller, Sep 18 2005

Keywords

• nonn

Links

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

Crossrefs

Cf. A022337, A051037, A112765, A112760, A112761.

Programs

Mathematica

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

Formula

a(n) = A112765(A051037(n));

a(n) = A112759(n) - A112760(n) - A112761(n).