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A185658 Primes of the form 43*n^2 + 3*n + 1. 2
41, 47, 167, 179, 379, 397, 677, 701, 1061, 1091, 1531, 1567, 2087, 2129, 2729, 2777, 3457, 3511, 4271, 5171, 5237, 6229, 7229, 7307, 8387, 9631, 9721, 11057, 12377, 12479, 13879, 15467, 15581, 20747, 20879, 22679, 22817 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Also primes of the form (n^2 + n + 41) / 43. Note that in the form 43n^2 + 3n + 1, both positive and negative n must be considered.

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..10000

MATHEMATICA

a={}; Do[p=(n^2+n+41)/43; If[PrimeQ[p], AppendTo[a, p]], {n, 10^4}]; Print[a];

PROG

(PARI) for(n=1, 1e2, if(isprime(t=43*n^2-3*n+1), print1(t", ")); if(isprime(t=43*n^2+3*n+1), print1(t", "))) \\ Charles R Greathouse IV, Feb 27 2011

CROSSREFS

Cf. A185657.

Sequence in context: A043151 A043931 A139219 * A074485 A039383 A043206

Adjacent sequences:  A185655 A185656 A185657 * A185659 A185660 A185661

KEYWORD

nonn,easy

AUTHOR

Michel Lagneau, Feb 08 2011

STATUS

approved

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Last modified December 2 13:15 EST 2021. Contains 349444 sequences. (Running on oeis4.)