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A161396 a(n) = the smallest positive integer that contains the same number of 1's as n when a(n) and n are written in binary, is not coprime to n, and is not a divisor of n. 2
4, 6, 8, 10, 9, 14, 16, 6, 6, 22, 9, 26, 21, 27, 32, 34, 10, 38, 6, 14, 14, 46, 9, 35, 14, 15, 21, 58, 27, 62, 64, 6, 6, 14, 10, 74, 14, 15, 6, 82, 22, 86, 14, 27, 30, 94, 9, 14, 14, 15, 14, 106, 15, 110, 21, 15, 30, 118, 27, 122, 93, 111, 128, 10, 9, 134, 6 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

LINKS

Rémy Sigrist, Table of n, a(n) for n = 2..10000

EXAMPLE

6_10 (6 in decimal) is 110_2 (110 in binary). 9_10 = 1001_2, which contains the same number of ones in the binary expansion. 9 isn't coprime to 6; they share prime factor 3 and 9 isn't a divisor of 6. No positive integer less than 9 has these properties. Therefore, a(6) = 9.

CROSSREFS

Cf. A145256, A161397

Sequence in context: A191488 A162600 A071537 * A145256 A087789 A071830

Adjacent sequences:  A161393 A161394 A161395 * A161397 A161398 A161399

KEYWORD

base,nonn

AUTHOR

Leroy Quet, Jun 09 2009

EXTENSIONS

Offset corrected and more terms from Rémy Sigrist, Apr 15 2017

STATUS

approved

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Last modified July 28 17:15 EDT 2021. Contains 346335 sequences. (Running on oeis4.)