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A155962
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Numbers n with property that 3*(2n)^2+1 and 1*(2n)^2+3 are primes.
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1
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1, 4, 11, 32, 56, 73, 80, 109, 122, 143, 158, 175, 182, 217, 256, 262, 280, 284, 290, 308, 343, 347, 403, 431, 434, 437, 535, 581, 598, 619, 655, 665, 928, 973, 980, 1018, 1036, 1046, 1096, 1120, 1159, 1207, 1222, 1235, 1267, 1382, 1393, 1439, 1460, 1463, 1501
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OFFSET
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1,2
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COMMENTS
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LINKS
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EXAMPLE
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n=1, {3*(2n)^2+1, 1*(2n)^2+3}={13,7};
n=4, {3*(2n)^2+1, 1*(2n)^2+3}={193,67};
n=11, {3*(2n)^2+1, 1*(2n)^2+3}={1453,487};
n=32, {3*(2n)^2+1,1*(2n)^2+3}={12289,4099}.
Resulting primes are congruent to 1 mod 3.
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MATHEMATICA
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Select[Range[1600], AllTrue[{3(2#)^2+1, (2#)^2+3}, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, May 30 2016 *)
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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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All the terms in the b-file had to be divided by 2. Corrected by N. J. A. Sloane, Aug 31 2009.
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STATUS
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approved
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