A025663 Exponent of 6 (value of i) in n-th number of form 6^i*10^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, 0, 9, 4, 8, 3, 7, 2, 6, 1, 10, 5, 0, 9, 4, 8, 3, 7, 2, 11, 6, 1, 10, 5, 0, 9, 4, 8, 3, 12, 7, 2, 11, 6, 1, 10, 5, 0, 9, 4, 13, 8, 3, 12, 7, 2, 11, 6, 1, 10, 5, 14, 0, 9, 4, 13, 8, 3, 12, 7, 2, 11, 6

Offset

1,4

Links

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

Formula

a(n) = A122841(A025629(n)). - Amiram Eldar, Nov 08 2025

Mathematica

seq[lim_] := IntegerExponent[Flatten[Table[6^i*10^j, {i, 0, Log[6, lim]}, {j, 0, Log10[lim/6^i]}]] // Sort, 6]; seq[10^12] (* Amiram Eldar, Nov 08 2025 *)

Crossrefs

Cf. A025629, A025688, A122841.

Sequence in context: A025652 A025662 A025640 * A025647 A025653 A131103

Adjacent sequences: A025660 A025661 A025662 * A025664 A025665 A025666

Keyword

nonn,easy

Author

David W. Wilson

Status

approved