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_Roger L. Bagula (rlbagulatftn(AT)yahoo.com), _, Apr 16 2006
Edited and extended by _N. J. A. Sloane (njas(AT)research.att.com), _, Apr 17 2006
nonn,new
nonn
Edited and extended by N. J. A. Sloane (njas, (AT)research.att.com), Apr 17 2006
Primes of the form n^2+5n+c (n>=0), where c=3 for even n and c=-3 for odd n.
3, 17, 47, 107, 173, 269, 503, 641, 809, 983, 1187, 1637, 2441, 2753, 4157, 4547, 4967, 5393, 5849, 6311, 6803, 7829, 8363, 9497, 11981, 12653, 13331, 14753, 15497, 17027, 22943, 26723, 29753, 31859, 32933, 38609, 39791, 42221, 47297, 49943, 58313
1,1
Alternating Euler quadratic prime generating polynomial.
Harvey Cohn, Advanced Number Theory,Dover, New York, 1962, page 155.
f[n_] := If[Mod[n, 2] == 1, n^2 + 5*n - 3, n^2 + 5*n + 3] b = Flatten[Table[If[PrimeQ[f[n]] == True, f[n], {}], {n, 1, 100}]]
(PARI) m=250; for(n=1, m, k=n^2+5*n+3-6*(n%2); if(isprime(k), print1(k, ", ")))
nonn,new
Roger L. Bagula (rlbagulatftn(AT)yahoo.com), Apr 16 2006
Edited and extended by njas, Apr 17 2006
approved