A117012 - OEIS

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A117012

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

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Alternating Euler quadratic prime generating polynomial.

REFERENCES

Harvey Cohn, Advanced Number Theory,Dover, New York, 1962, page 155.

LINKS

Table of n, a(n) for n=1..41.

MATHEMATICA

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}]]

PROG