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A168154
Numbers n such that the sum of binary digits in prime(1), ..., prime(n) is prime.
1
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
KEYWORD
nonn,base,easy
AUTHOR
M. F. Hasler, Nov 20 2009
EXTENSIONS
Terms corrected by Charles R Greathouse IV, Mar 29 2013
STATUS
approved