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A097434
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Value of C in y = x^2 + 5x + C such that y is prime for all x = 0 to 3.
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1
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5, 17, 23, 47, 83, 167, 227, 257, 443, 563, 593, 677, 1277, 1283, 1613, 1973, 2333, 2837, 2903, 3533, 5393, 5843, 6197, 6263, 6977, 7523, 8087, 8363, 11807, 12473, 12893, 13463, 13907, 14537, 14717, 15077, 15263, 15377, 17093, 17327, 19913
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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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a(2) = 17: y = x^2+5x+17.
If x = 0; y = 0+0+17 = 17, which is prime.
If x = 1; y = 1+5+17 = 23, which is prime.
If x = 2; y = 4+10+17 = 31, which is prime.
If x = 3; y = 9+15+17 = 41, which is prime.
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PROG
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(PARI) isok(n) = {for (x=0, 3, if (! isprime(x^2+5*x+n), return (0)); ); return (1); } \\ Michel Marcus, Aug 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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STATUS
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approved
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