

A063565


Smallest positive number k such that 2^k contains n.


9



10, 4, 1, 5, 2, 8, 4, 15, 3, 12, 10, 40, 7, 17, 18, 21, 4, 27, 30, 13, 11, 18, 43, 41, 10, 8, 18, 15, 7, 32, 22, 17, 5, 25, 27, 25, 16, 30, 14, 42, 12, 22, 19, 22, 18, 28, 42, 31, 11, 32, 52, 9, 19, 16, 25, 16, 8, 20, 33, 33, 23, 58, 18, 14, 6, 16, 46, 24, 15, 34, 29, 21, 17, 30
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OFFSET

0,1


LINKS

Chai Wah Wu, Table of n, a(n) for n = 0..10000
Popular Computing (Calabasas, CA), Two Tables, Vol. 1, (No. 9, Dec 1973), page PC916.


EXAMPLE

a(7) = 15 because 2^15 = 32768.


MATHEMATICA

a = {}; Do[k = 1; While[ StringPosition[ ToString[2^k], ToString[n] ] == {}, k++ ]; a = Append[a, k], {n, 0, 50} ]; a


PROG

(Python)
def A063565(n):
....s, k, k2 = str(n), 1, 2
....while True:
........if s in str(k2):
............return k
........k += 1
........k2 *= 2 # Chai Wah Wu, Jun 20 2015


CROSSREFS

Apart from initial term, a duplicate of A030000.
Cf. A006889, A131535, A131536, A259089, A063565, A259091, A259092.
Sequence in context: A089478 A028967 A097530 * A177390 A082961 A065194
Adjacent sequences: A063562 A063563 A063564 * A063566 A063567 A063568


KEYWORD

base,nonn


AUTHOR

Robert G. Wilson v, Aug 10 2001


EXTENSIONS

More terms from Hans Havermann


STATUS

approved



