A097660 Number of zeros in decimal representation of 1001^n.

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

Author

Reinhard Zumkeller, Aug 18 2004

Keywords

• nonn
• base

Comments

a(n) = A055641(A097659(n)).

Examples

			a(2)=4, as A097659(1)=1001^2=1002001 contains four zeros.
		

Programs

Mathematica

DigitCount[#,10,0]&/@(1001^Range[0,75])  (* Harvey P. Dale, Apr 26 2011 *)