A025660 Exponent of 6 (value of i) in n-th number of form 6^i*7^j.

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

Offset

1,4

Links

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

Formula

a(n) = A122841(A025626(n)). - Amiram Eldar, Nov 08 2025

Mathematica

seq[lim_] := IntegerExponent[Flatten[Table[6^i*7^j, {i, 0, Log[6, lim]}, {j, 0, Log[7, lim/6^i]}]] // Sort, 6]; seq[10^11] (* Amiram Eldar, Nov 08 2025 *)

Crossrefs

Cf. A025626, A025668, A122841.

Sequence in context: A025669 A025676 A025683 * A025677 A025651 A330238

Adjacent sequences: A025657 A025658 A025659 * A025661 A025662 A025663

Keyword

nonn,easy

Author

David W. Wilson

Status

approved