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A097660
Number of zeros in decimal representation of 1001^n.
1
0, 2, 4, 6, 8, 10, 10, 10, 12, 10, 12, 8, 8, 6, 18, 14, 10, 10, 8, 5, 12, 14, 9, 7, 10, 18, 14, 13, 15, 13, 15, 10, 14, 12, 17, 16, 17, 15, 13, 21, 24, 15, 9, 16, 12, 22, 20, 21, 20, 16, 19, 16, 21, 20, 25, 20, 20, 21, 26, 19, 20, 19, 22, 19, 17, 23, 28, 24, 22, 20, 27, 26, 25
OFFSET
0,2
COMMENTS
a(n) = A055641(A097659(n)).
EXAMPLE
a(2)=4, as A097659(1)=1001^2=1002001 contains four zeros.
MATHEMATICA
DigitCount[#, 10, 0]&/@(1001^Range[0, 75]) (* Harvey P. Dale, Apr 26 2011 *)
CROSSREFS
Sequence in context: A061243 A079431 A081472 * A238898 A176995 A225793
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Aug 18 2004
STATUS
approved