A247151 Numbers n such that abs(36*n^2 - 810*n + 2753) is prime.

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 46, 47, 48, 49, 50, 51, 52, 55, 56, 57, 59, 61, 62, 64, 65, 66, 69, 70, 71, 73, 78, 80, 82, 83, 84, 85, 88, 90

Offset

1,3

Comments

For 5, 6,...,18, the expression is negative, so the absolute value must be considered to get a (positive) prime. Thereafter, for 45, 53, 54, 58, 60, 63, 67, 68, 72, 74,... the values are composite. - M. F. Hasler, Jan 18 2015

Links

Table of n, a(n) for n=1..73.

Eric Weisstein's World of Mathematics, Prime-Generating Polynomial

Mathematica

Select[Range[0, 100], PrimeQ[(36 #^2 - 810 # + 2753)] &]

Prog

(Magma) [n: n in [0..100] | IsPrime(36*n^2-810*n+2753)];
(PARI) for(n=0, 999, isprime(abs(36*n^2-810*n+2753))&&print1(n", "))

Crossrefs

Cf. A050268 (associated primes).

Sequence in context: A272302 A272443 A272437 * A267069 A366188 A002837

Adjacent sequences: A247148 A247149 A247150 * A247152 A247153 A247154

Keyword

nonn,easy

Author

Vincenzo Librandi, Nov 21 2014

Extensions

Corrected by M. F. Hasler, Jan 18 2015

Status

approved