A084345 Numbers with a nonprime number of 1's in their binary expansion (complement of A052294).

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

Offset: 1

Author

Zak Seidov Jun 22 2003

Keywords

• easy
• nonn
• base

Examples

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

Links

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

Crossrefs

Cf. A052294.

Cf. A010051, A000120.

Programs

Haskell

a084345 n = a084345_list !! (n-1)
a084345_list = filter ((== 0) . a010051' . a000120) [0..]
-- Reinhard Zumkeller, Aug 28 2013, Nov 16 2012

Mathematica

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

PARI

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

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