A063568 5^a(n) is the smallest positive power of 5 having n in its decimal representation.

8, 3, 2, 5, 11, 1, 4, 7, 7, 8, 14, 23, 3, 30, 12, 6, 20, 15, 22, 9, 13, 33, 13, 22, 12, 2, 18, 37, 11, 17, 15, 5, 19, 35, 19, 14, 20, 21, 18, 8, 12, 12, 37, 20, 12, 17, 18, 21, 11, 26, 23, 14, 16, 9, 30, 23, 6, 15, 16, 24, 24

Offset

0,1

Links

Harvey P. Dale, Table of n, a(n) for n = 0..1000

Mathematica

a = {}; Do[k = 1; While[ StringPosition[ ToString[5^k], ToString[n]] == {}, k++ ]; a = Append[a, k], {n, 0, 60} ]; a
sp5[n_]:=Module[{k=1, idn=IntegerDigits[n]}, While[SequenceCount[ IntegerDigits[ 5^k], idn] == 0, k++]; k]; Array[sp5, 70, 0] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Aug 05 2019 *)

Crossrefs

Essentially the same as A062522.

Sequence in context: A273556 A346713 A154014 * A302138 A198494 A100668

Adjacent sequences: A063565 A063566 A063567 * A063569 A063570 A063571

Keyword

base,nonn

Author

Robert G. Wilson v, Aug 10 2001

Status

approved