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A095313

Primes in whose binary expansion the number of 1-bits is <= 6 + number of 0-bits.

2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269

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OFFSET

1,1

COMMENTS

Differs from primes (A000040) first time at n=31, where a(31)=131, while A000040(31)=127, as 127 whose binary expansion is 1111111, with 7 1-bits and no 0-bits is the first prime excluded from this sequence.

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

A. Karttunen and J. Moyer: C-program for computing the initial terms of this sequence

MATHEMATICA

Select[Prime[Range[100]], DigitCount[#, 2, 1]<= DigitCount[#, 2, 0]+6&] (* Harvey P. Dale, Aug 18 2016 *)

PROG

(PARI)forprime(p=2, 269, v=binary(p); s=0; for(k=1, #v, s+=if(v[k]==1, +1, -1)); if(s<=6, print1(p, ", "))) \\ Washington Bomfim, Jan 13 2011

CROSSREFS

Complement of A095312 in A000040. Subset: A095285, from which it differs first time at n=42, where a(42)=191 (10111111 in binary), while A095285(42)=193 (11000001 in binary). Cf. also A095333.

Sequence in context: A100725 A050260 A095316 * A095285 A393798 A163849

Adjacent sequences: A095310 A095311 A095312 * A095314 A095315 A095316

KEYWORD

nonn,base,easy

AUTHOR

Antti Karttunen, Jun 04 2004

STATUS

approved

URL: https://oeis.org/A095313

⇱ A095313 - OEIS