A025662 Exponent of 6 (value of i) in n-th number of form 6^i*9^j.

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

Offset

1,4

Links

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

Formula

a(n) = A122841(A025628(n)). - Amiram Eldar, Nov 08 2025

Mathematica

seq[lim_] := IntegerExponent[Flatten[Table[6^i*9^j, {i, 0, Log[6, lim]}, {j, 0, Log[9, lim/6^i]}]] // Sort, 6]; seq[10^12] (* Amiram Eldar, Nov 08 2025 *)

Crossrefs

Cf. A025628, A025680, A122841.

Sequence in context: A025661 A025671 A025652 * A025640 A025663 A025647

Adjacent sequences: A025659 A025660 A025661 * A025663 A025664 A025665

Keyword

nonn,easy

Author

David W. Wilson

Status

approved