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A213856
Least m such that m!*5^m >= n!.
1
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
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
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Jul 17 2012
STATUS
approved