A025657 Exponent of 6 (value of j) in n-th number of form 3^i*6^j.

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

Offset

1,7

Comments

Differs from A025686 at a(114).

Links

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

Formula

a(n) = A122841(A025614(n)). - Amiram Eldar, Nov 08 2025

Mathematica

seq[lim_] := SortBy[Flatten[Table[{i, j}, {i, 0, Log[3, lim]}, {j, 0, Log[6, lim/3^i]}], 1], 3^#[[1]]*6^#[[2]] &][[;; , 2]]; seq[10^9] (* Amiram Eldar, Nov 08 2025 *)

Crossrefs

Cf. A025614, A025686, A122841.

A025641 is the exponent of 3 (value of i).

Sequence in context: A140575 A091917 A391262 * A025686 A215345 A022329

Adjacent sequences: A025654 A025655 A025656 * A025658 A025659 A025660

Keyword

nonn,easy

Author

David W. Wilson

Status

approved