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A161607 Positive integers k that are coprime to the value of the reversal of k's representation in binary. 1
1, 2, 4, 8, 11, 13, 16, 19, 22, 23, 25, 26, 29, 32, 37, 38, 41, 43, 44, 46, 47, 50, 52, 53, 55, 58, 59, 61, 64, 67, 71, 74, 76, 77, 79, 82, 83, 86, 88, 89, 91, 92, 94, 97, 100, 101, 103, 104, 106, 109, 110, 113, 115, 116, 118, 121, 122, 128, 131, 134, 137, 139, 142, 143 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

By "reversal" of k's representation in binary, it is meant: write k in binary, reverse the order of its digits, and read the result as a binary value.

LINKS

Table of n, a(n) for n=1..64.

MAPLE

A030101 := proc(n) local bdgs; bdgs := convert(n, base, 2) ; add( op(-i, bdgs)*2^(i-1), i=1..nops(bdgs)) ; end: A161607 := proc(n) option remember ; local a; if n = 1 then 1; else for a from procname(n-1)+1 do if gcd(A030101(a), a) = 1 then RETURN(a) ; fi; od: fi; end: seq(A161607(n), n=1..100) ; # R. J. Mathar, Jul 04 2009

CROSSREFS

Cf. A030101.

Sequence in context: A243181 A236206 A078649 * A318206 A022442 A308163

Adjacent sequences:  A161604 A161605 A161606 * A161608 A161609 A161610

KEYWORD

base,nonn

AUTHOR

Leroy Quet, Jun 14 2009

EXTENSIONS

More terms from R. J. Mathar, Jul 04 2009

STATUS

approved

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Last modified August 7 23:38 EDT 2020. Contains 336279 sequences. (Running on oeis4.)