A161398 a(n) = the smallest divisor of n that contains the same number of 1's as n when both numbers are written in binary.

1, 1, 3, 1, 5, 3, 7, 1, 3, 5, 11, 3, 13, 7, 15, 1, 17, 3, 19, 5, 7, 11, 23, 3, 25, 13, 27, 7, 29, 15, 31, 1, 3, 17, 7, 3, 37, 19, 39, 5, 41, 7, 43, 11, 15, 23, 47, 3, 7, 25, 51, 13, 53, 27, 55, 7, 57, 29, 59, 15, 61, 31, 63, 1, 5, 3, 67, 17, 69, 7, 71, 3, 73, 37, 15, 19, 77, 39, 79, 5, 81

Offset: 1

Author

Leroy Quet, Jun 09 2009

Keywords

• base
• nonn

Links

• Paul Tek, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A161399.

Extensions

More terms from Sean A. Irvine, Oct 22 2009