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A238699
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Primes p such that 2p + 3 and 4p + 3 are both prime.
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1
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2, 5, 7, 17, 19, 47, 67, 89, 157, 227, 229, 307, 349, 439, 467, 487, 509, 599, 647, 797, 929, 1039, 1187, 1217, 1237, 1259, 1307, 1427, 1447, 1567, 1789, 2027, 2309, 2467, 2539, 2707, 2789, 2819, 3167, 3457, 3499, 3659, 3877, 3919, 4057, 4079, 4157, 4289, 4297
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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89 is in the sequence because 2*89 + 3 = 181 and 4*89 + 3 = 359 are both prime.
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MATHEMATICA
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Select[Prime[Range[600]], AllTrue[{2#+3, 4#+3}, PrimeQ]&] (* Harvey P. Dale, Dec 24 2023 *)
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PROG
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(Magma) [p: p in PrimesUpTo(4500) | IsPrime(2*p+3) and IsPrime(4*p+3)]; // Bruno Berselli, Mar 03 2014
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CROSSREFS
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KEYWORD
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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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