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A207838
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Numbers k such that 5*k^4 + 1 is prime.
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2
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6, 12, 114, 120, 324, 336, 390, 420, 498, 504, 540, 672, 756, 768, 840, 852, 876, 1014, 1062, 1092, 1122, 1170, 1188, 1248, 1266, 1314, 1344, 1398, 1440, 1470, 1524, 1758, 1770, 1818, 1860, 1968, 2028, 2046, 2088, 2184, 2190, 2232, 2262, 2268, 2304, 2382, 2430
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OFFSET
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1,1
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COMMENTS
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All terms are multiples of 6.
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LINKS
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FORMULA
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MATHEMATICA
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Select[Range[2440], PrimeQ[5 #^4 + 1] &] (* by definition *)
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PROG
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(PARI) for(n=1, 406, r=6480*n^4+1; if(isprime(r), print1(6*n", ")));
(Magma) [6*n: n in [1..406] | IsPrime(6480*n^4+1)];
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CROSSREFS
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Cf. A207837 (primes of the form 5*k^4+1).
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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