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A143909 A positive integer n is included if the number of digits in the binary representation of n is a multiple of the number of zeros in the binary representation of n. 1
2, 5, 6, 9, 10, 11, 12, 13, 14, 23, 27, 29, 30, 35, 37, 38, 39, 41, 42, 43, 44, 45, 46, 47, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 95, 111, 119, 123, 125, 126, 135, 139, 141, 142, 147, 149, 150, 153, 154, 156, 159, 163, 165, 166, 169, 170, 172, 175, 177 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

FORMULA

{n: A080791(n) | A070939(n)}. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Sep 05 2008]

MAPLE

A070939 := proc(n) max(1, 1+floor(ilog2(n))) ; end: A080791 := proc(n) local dgs ; dgs := convert(n, base, 2) ; nops(dgs)-add(i, i=dgs) ; end: isA143909 := proc(n) zs := A080791(n) ; if zs > 0 then if A070939(n) mod zs = 0 then true ; else false ; fi; else false ; fi; end: for n from 1 to 500 do if isA143909(n) then printf("%d, ", n) ; fi; od: [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Sep 05 2008]

MATHEMATICA

Select[Range[200], DigitCount[ #, 2, 0] > 0 && Mod[Length[IntegerDigits[ #, 2]], DigitCount[ #, 2, 0]] == 0 &] [From Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Sep 05 2008]

CROSSREFS

A096199

Sequence in context: A097685 A136369 A007573 * A139454 A171888 A028946

Adjacent sequences:  A143906 A143907 A143908 * A143910 A143911 A143912

KEYWORD

base,nonn

AUTHOR

Leroy Quet Sep 04 2008

EXTENSIONS

More terms from Stefan Steinerberger (stefan.steinerberger(AT)gmail.com) and R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Sep 05 2008

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Last modified February 16 21:51 EST 2012. Contains 205978 sequences.