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A118737
Number of zeros in binary expansion of 5^n.
2
0, 1, 2, 1, 5, 6, 7, 9, 7, 8, 13, 11, 15, 17, 16, 15, 18, 20, 18, 26, 21, 20, 27, 27, 26, 40, 30, 30, 37, 32, 33, 39, 36, 43, 37, 42, 40, 44, 51, 45, 40, 42, 49, 48, 51, 52, 57, 61, 58, 54, 59, 59, 67, 60, 68, 54, 70, 66, 61, 72, 79, 65, 70, 66, 63, 73, 67, 71, 76, 72, 80, 86, 78
OFFSET
0,3
LINKS
FORMULA
a(n) + A118738(n) = A061785(n)+1 for n >= 1. - Robert Israel, Dec 24 2017
a(n) = A023416(A000351(n)). - Felix Fröhlich, Dec 24 2017
MAPLE
seq(numboccur(0, convert(5^n, base, 2)), n=0..100); # Robert Israel, Dec 24 2017
MATHEMATICA
a[n_] := DigitCount[5^n, 2, 0]; Table[a[n], {n, 0, 72}] (* Ray Chandler, Sep 29 2006 *)
DigitCount[5^Range[0, 80], 2, 0] (* Harvey P. Dale, Aug 30 2021 *)
PROG
(PARI) a(n) = #binary(5^n)-hammingweight(5^n) \\ Felix Fröhlich, Dec 24 2017
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Zak Seidov, May 22 2006
STATUS
approved