A213856 Least m such that m!*5^m >= n!.

1, 1, 2, 2, 3, 3, 4, 5, 5, 6, 7, 8, 8, 9, 10, 10, 11, 12, 13, 13, 14, 15, 15, 16, 17, 18, 18, 19, 20, 21, 21, 22, 23, 23, 24, 25, 26, 26, 27, 28, 29, 29, 30, 31, 32, 32, 33, 34, 35, 36, 36, 37, 38, 39, 39, 40, 41, 42, 42, 43, 44, 45, 45, 46

Offset

1,3

Links

Clark Kimberling, Table of n, a(n) for n = 1..1000

Example

a(6) = 3 because (5^2)*2! < 6! <= (5^3)*3!.

Mathematica

Table[m=1; While[n!>(5^m)*m!, m++]; m, {n, 1, 100}]
Module[{nn=70, m}, mt=Table[{m, m! 5^m}, {m, nn}]; Table[SelectFirst[mt, #[[2]] >= n!&], {n, nn}]][[All, 1]] (* Harvey P. Dale, Sep 23 2018 *)

Crossrefs

Cf. A213855.

Sequence in context: A083479 A112231 A334742 * A173329 A369113 A241951

Adjacent sequences: A213853 A213854 A213855 * A213857 A213858 A213859

Keyword

nonn,easy

Author

Clark Kimberling, Jul 17 2012

Status

approved