A084345 - OEIS

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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

(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)