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A144214
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Primes with both a prime number of 0's and a prime number of 1's in their binary representations.
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5
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17, 19, 37, 41, 79, 103, 107, 109, 131, 137, 151, 157, 167, 173, 179, 181, 193, 199, 211, 227, 229, 233, 241, 257, 367, 379, 431, 439, 443, 463, 487, 491, 499, 521, 541, 557, 563, 569, 577, 587, 601, 607, 613, 617, 631, 641, 647, 653, 659, 661, 677, 701, 709
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OFFSET
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1,1
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LINKS
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EXAMPLE
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79, a prime, in binary is 1001111. This has two 0's and has five 1's. Since both two and five are primes, 79 is included in the sequence.
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MAPLE
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A080791 := proc(n) local i, dgs ; dgs := convert(n, base, 2) ; nops(dgs)-add(i, i=dgs) ; end: A000120 := proc(n) local i, dgs ; dgs := convert(n, base, 2) ; add(i, i=dgs) ; end: isA144214 := proc(n) local no0, no1 ; no0 := A080791(n) ; no1 := A000120(n) ; isprime(n) and isprime(no0) and isprime(no1) ; end: for n from 1 to 1200 do if isA144214(n) then printf("%d, ", n) ; fi; od: # R. J. Mathar, Sep 17 2008
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MATHEMATICA
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PROG
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(Python)
from sympy import isprime
def ok(n): return isprime(c:=n.bit_count()) and isprime(n.bit_length()-c) and isprime(n)
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CROSSREFS
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KEYWORD
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base,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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