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A137581 Number of inner zeros in decimal representation of n!. 2
0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 2, 2, 0, 1, 1, 1, 2, 3, 3, 3, 4, 1, 2, 3, 2, 3, 4, 1, 2, 0, 3, 1, 4, 1, 2, 4, 8, 4, 0, 6, 4, 4, 3, 3, 6, 1, 4, 4, 7, 6, 6, 5, 6, 5, 4, 7, 4, 6, 5, 12, 6, 7, 6, 5, 8, 7, 10, 6, 4, 9, 7, 19, 7, 7, 6, 14, 7, 11, 8, 8, 9, 11, 8, 16, 8, 7, 8, 14, 7, 8, 8, 11, 16, 10, 14, 4, 13 (list; graph; refs; listen; history; internal format)
OFFSET

0,13

COMMENTS

a(n) = A027869(n) - A027868(n);

a(A137582(n)) = 0.

First occurrence of k=0.., or zero if impossible: 1, 8, 13, 20, 23, 54, 42, 51, 39, 72, 69, 80, 62, 99, 78, 120, 86, 108, 0, 74, 106, ..., . - Robert G. Wilson v.

LINKS

Robert G. Wilson v, Table of n, a(n) for n = 0..10000.

Index entries for sequences related to factorial numbers.

MATHEMATICA

f[n_] := f[n] = Block[{a = n!}, While[Mod[a, 10] == 0, a = a/10]; Count[ IntegerDigits@a, 0]]; Table[f@n, {n, 0, 98}] (* Robert G. Wilson v (rgwv(AT)rgwv.com), Jan 28 2008 *)

CROSSREFS

Cf. A000142.

Sequence in context: A089385 A124407 A206442 * A156311 A189463 A113414

Adjacent sequences:  A137578 A137579 A137580 * A137582 A137583 A137584

KEYWORD

nonn,base

AUTHOR

Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Jan 27 2008

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Last modified February 16 20:58 EST 2012. Contains 205967 sequences.