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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
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
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Jun 17 2002
STATUS
approved