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A084345 Numbers with a nonprime number of 1's in their binary expansion (complement of A052294). 6
0, 1, 2, 4, 8, 15, 16, 23, 27, 29, 30, 32, 39, 43, 45, 46, 51, 53, 54, 57, 58, 60, 63, 64, 71, 75, 77, 78, 83, 85, 86, 89, 90, 92, 95, 99, 101, 102, 105, 106, 108, 111, 113, 114, 116, 119, 120, 123, 125, 126, 128, 135, 139, 141, 142, 147, 149, 150, 153, 154, 156, 159, 163 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

EXAMPLE

15 is in the sequence because 15_10=1111_2 and 1+1+1+1=4 is composite.

MATHEMATICA

Select[Range[200], !PrimeQ[DigitCount[#, 2, 1]]&] (* Harvey P. Dale, Jan 21 2013 *)

PROG

(PARI) for(n=0, 200, b=binary(n); if(!isprime(sum(m=1, matsize(b)[2], b[m])), print1(n, ", ")))

(Haskell)

a084345 n = a084345_list !! (n-1)

a084345_list = filter ((== 0) . a010051' . a000120) [0..]

-- Reinhard Zumkeller, Aug 28 2013, Nov 16 2012

CROSSREFS

Cf. A052294.

Cf. A010051, A000120.

Sequence in context: A002954 A019278 A267894 * A084561 A277166 A078613

Adjacent sequences:  A084342 A084343 A084344 * A084346 A084347 A084348

KEYWORD

easy,nonn,base

AUTHOR

Zak Seidov Jun 22 2003

EXTENSIONS

More terms from Rick L. Shepherd, Jun 23 2003

Term 0 added by Michel Marcus, Aug 26 2013

b-file adjusted by Reinhard Zumkeller, Aug 28 2013

STATUS

approved

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Last modified September 29 07:08 EDT 2020. Contains 337425 sequences. (Running on oeis4.)