A062524 7^a(n) is smallest nonnegative power of 7 containing the string 'n'.

4, 0, 4, 3, 2, 7, 5, 1, 5, 2, 13, 6, 12, 12, 19, 15, 5, 6, 19, 11, 12, 22, 14, 7, 4, 30, 11, 23, 10, 16, 14, 19, 11, 16, 3, 7, 9, 19, 12, 17, 4, 12, 27, 3, 18, 21, 32, 10, 8, 2, 15, 17, 10, 9, 7, 21, 15, 8, 21, 18, 9, 15, 18, 17, 6, 27, 20, 11, 5, 16, 33, 27, 12, 11, 11, 10

Offset

0,1

Comments

See A176767 for the actual powers 7^a(n). - M. F. Hasler, Oct 03 2014

Links

Table of n, a(n) for n=0..75.

Mathematica

Table[k = 0; While[ StringPosition[ ToString[7^k], ToString[n] ] == {}, k++ ]; k, {n, 0, 75} ]

Crossrefs

Cf. A030000.

Essentially the same as A063570.

Sequence in context: A361618 A367873 A016680 * A152856 A031362 A378012

Adjacent sequences: A062521 A062522 A062523 * A062525 A062526 A062527

Keyword

base,nonn

Author

Robert G. Wilson v, Jun 24 2001

Status

approved