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A115454 Composite positive integers written in base 2. 3
100, 110, 1000, 1001, 1010, 1100, 1110, 1111, 10000, 10010, 10100, 10101, 10110, 11000, 11001, 11010, 11011, 11100, 11110, 100000, 100001, 100010, 100011, 100100, 100110, 100111, 101000, 101010, 101100, 101101, 101110, 110000, 110001 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

If n is in the sequence then so is 10 * n. - David A. Corneth, Aug 17 2018

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = A007088(A002808(n)).

MAPLE

map(convert, remove(isprime, [$4..200]), binary); # Robert Israel, Aug 17 2018

MATHEMATICA

For[n = 2, n < 50, n++, If[Not[PrimeQ[n]], Print[BaseForm[n, 2]]]] (* Stefan Steinerberger, Jan 24 2006 *)

PROG

(PARI) lista(nn) = forcomposite(n=1, nn, print1(fromdigits(binary(n), 10), ", ")); \\ Michel Marcus, Aug 17 2018

CROSSREFS

Cf. A002808, A007088, A004676.

Sequence in context: A033828 A162530 A204590 * A122466 A066511 A281193

Adjacent sequences:  A115451 A115452 A115453 * A115455 A115456 A115457

KEYWORD

base,nonn

AUTHOR

Leroy Quet, Jan 22 2006

EXTENSIONS

More terms from Stefan Steinerberger, Jan 24 2006

STATUS

approved

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Last modified February 26 17:22 EST 2021. Contains 341632 sequences. (Running on oeis4.)