

A085769


Total number of zeros in the decimal expansions of 2^n and 5^n.


0



0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 2, 2, 1, 1, 1, 1, 0, 1, 2, 2, 2, 3, 2, 1, 2, 2, 2, 3, 1, 1, 2, 0, 3, 3, 2, 2, 4, 3, 5, 2, 3, 4, 5, 8, 5, 5, 6, 4, 4, 4, 8, 9, 5, 7, 4, 3, 1, 5, 6, 8, 8, 9, 10, 7, 7, 5, 8, 11, 11, 7, 8, 5, 4, 4, 6, 5, 6, 8, 10, 7, 6, 7, 4, 2, 4, 9, 9, 7, 9, 9, 8, 10, 10, 5, 5, 8, 11, 14, 18
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OFFSET

1,12


COMMENTS

10^33 is believed to be the largest power of 10 that can be expressed as the product of 2 numbers which contain no zero digits.


REFERENCES

C. Stanley Ogilvy and John T. Anderson, Excursions in Number Theory. Dover. New York: 1988. Page 89.
C. Pickover, Wonders of Numbers, Oxford University Press, NY, 2001, pp. 201202, 353.


LINKS

C. A. Pickover, "Wonders of Numbers, Adventures in Mathematics, Mind and Meaning," Zentralblatt review


EXAMPLE

a(58)=1 because 10^58 = 288230376151711744 * 34694469519536141888238489627838134765625
and the latter two numbers contain only one zero between them.


CROSSREFS



KEYWORD

nonn,base


AUTHOR



STATUS

approved



