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A240676
Number of digits in the decimal expansion of n^7.
0
1, 1, 3, 4, 5, 5, 6, 6, 7, 7, 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13
OFFSET
0,3
FORMULA
a(n) = A055642(n^7) = A055642(A001015(n)).
EXAMPLE
a(1) = 1, because 1^7 = 1.
a(2) = 4, because 2^7 = 1024.
PROG
(PARI) a(n)=max(#digits(n^7), 1) \\ Charles R Greathouse IV, May 12 2014
CROSSREFS
Sequence in context: A358700 A307136 A339362 * A037038 A348133 A278375
KEYWORD
nonn,base,easy
AUTHOR
Michelle Tu, Apr 28 2014
STATUS
approved