A025647 Exponent of 4 (value of i) in n-th number of form 4^i*6^j.

0, 1, 0, 2, 1, 0, 3, 2, 1, 0, 4, 3, 2, 1, 5, 0, 4, 3, 2, 6, 1, 5, 0, 4, 3, 7, 2, 6, 1, 5, 0, 4, 8, 3, 7, 2, 6, 1, 5, 9, 0, 4, 8, 3, 7, 2, 6, 10, 1, 5, 9, 0, 4, 8, 3, 7, 11, 2, 6, 10, 1, 5, 9, 0, 4, 8, 12, 3, 7, 11, 2, 6, 10, 1, 5, 9, 0, 13, 4, 8, 12, 3, 7, 11, 2, 6, 10, 1, 14, 5, 9, 0, 13, 4, 8, 12, 3, 7, 11, 2

Offset: 1

Author

David W. Wilson

Keywords

• nonn

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000
• Index entries for sequences which agree for a long time but are different.

Crossrefs

Cf. A025618, A025658, A235127.

Differs from A025653 at a(2805).

Programs

Mathematica

With[{max = 10^10}, SortBy[Flatten[Table[{i, j}, {i, 0, Log[4, max]}, {j, 0, Log[6, max/4^i]}], 1], 4^#[[1]] * 6^#[[2]] &][[;; , 1]]] (* Amiram Eldar, Jul 09 2025 *)

Formula

a(n) = A235127(A025618(n)/6^A025658(n)). - Amiram Eldar, Jul 09 2025