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A072439 Primes prime(k) such that the number of binary 1's in prime(k) equals the number of binary 1's in k. 11
2, 5, 41, 67, 73, 83, 97, 113, 193, 197, 211, 269, 281, 283, 353, 389, 521, 523, 547, 563, 587, 593, 601, 647, 661, 691, 929, 937, 1061, 1063, 1097, 1109, 1117, 1123, 1289, 1319, 1361, 1381, 1489, 1549, 1559, 1567, 1571, 1579, 1597, 1801, 1873, 2069 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
FORMULA
A000120(a(n)) = A000120(A071600(n)) = A014499(n).
A090455(A049084(a(n))) = 0.
a(n) = A000040(A071600(n)).
EXAMPLE
In binary representation 13 and A000040(13)=41 have three 1's: 13='1101' and 41='101001', therefore 41 is a term.
MATHEMATICA
Prime[Select[Range[400], DigitCount[#, 2, 1] == DigitCount[Prime[#], 2, 1] &]] (* Amiram Eldar, Aug 03 2023 *)
PROG
(PARI) isok(p) = isprime(p) && ((hammingweight(p) == hammingweight(primepi(p)))); \\ Michel Marcus, Jun 14 2021
CROSSREFS
Sequence in context: A004096 A156152 A106885 * A286560 A002592 A054553
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Jun 17 2002
STATUS
approved

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Last modified March 29 03:41 EDT 2024. Contains 371264 sequences. (Running on oeis4.)