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A107295
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Numbers k such that prime(k^2) - k^2 is prime.
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0
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2, 4, 12, 14, 20, 42, 48, 56, 60, 88, 104, 120, 126, 134, 138, 160, 164, 182, 186, 204, 226, 254, 270, 276, 312, 316, 330, 336, 350, 382, 408, 410, 414, 422, 438, 448, 450, 480, 492, 494, 502, 522, 546, 568, 580, 596, 620, 624, 640, 650, 690, 696
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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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88 is in the sequence because prime(88^2) - 88^2 = prime(7744) - 7744 = 78977 - 7744 = 71233 = prime(7051).
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MATHEMATICA
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Select[Range[700], PrimeQ[Prime[#^2]-#^2]&] (* Harvey P. Dale, Jun 20 2015 *)
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PROG
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(PARI) isok(n) = isprime(prime(n^2) - n^2); \\ Michel Marcus, Oct 09 2013
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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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