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A096659
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Earliest value of C in y = x^2+(2n-1)x+C such that y is prime for all x = 0 to n.
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0
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2, 3, 3, 5, 23, 31, 47, 59, 13, 29, 17, 37, 23, 47, 73, 251, 281, 313, 347, 383, 421
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OFFSET
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0,1
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COMMENTS
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LINKS
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EXAMPLE
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Triangle of y, primes, starts:
2,
3, 7,
3, 9, 17,
5, 13, 23, 35,
23, 33, 45, 59, 75,
31, 43, 57, 73, 91, 111,
47, 61, 77, 95, 115, 137, 161,
59, 75, 93, 113, 135, 159, 185, 213,
...
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PROG
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(PARI) a(n) = C = 1; ok = 0; while (! ok, ok = 1; for (x = 0, n, if (! isprime(x^2+(2*n-1)*x+C), ok = 0; break; ); ); if (ok, return (C)); C++; ); \\ Michel Marcus, Aug 10 2013
(PARI) works(C, n)=for(x=1, n, if(!isprime(x^2+(2*n-1)*x+C), return(0))); 1
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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