A168154 Numbers n such that the sum of binary digits in prime(1), ..., prime(n) is prime.

2, 3, 5, 8, 9, 15, 18, 21, 28, 34, 35, 45, 51, 53, 68, 77, 84, 86, 87, 90, 92, 102, 113, 116, 119, 121, 130, 131, 137, 149, 164, 174, 178, 192, 205, 210, 220, 221, 238, 240, 241, 250, 255, 275, 315, 318, 324, 344, 345, 363, 369, 375, 381, 386, 396, 397, 398, 404

Offset

1,1

Comments

Indices of primes in A095375.

Links

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

Mathematica

Module[{nn=500, prs}, prs=Table[IntegerDigits[p, 2], {p, Prime[Range[nn]]}]; Select[Range[nn], PrimeQ[Total[Flatten[Take[prs, #]]]]&]] (* Harvey P. Dale, Aug 28 2021 *)

Prog

(PARI) s=0; for(n=1, 999, isprime(s+=norml2(binary(prime(n)))) & print1(n", "))
is_A168154(n)=isprime(A095375(n))
(PARI) s=n=0; forprime(p=2, 1e9, n++; if(isprime(s+=hammingweight(p)), print1(n", "))) \\ Charles R Greathouse IV, Mar 29 2013

Crossrefs

Cf. A168153.

Sequence in context: A104737 A286495 A295082 * A278334 A120057 A099422

Adjacent sequences: A168151 A168152 A168153 * A168155 A168156 A168157

Keyword

nonn,base,easy

Author

M. F. Hasler, Nov 20 2009

Extensions

Terms corrected by Charles R Greathouse IV, Mar 29 2013

Status

approved