A082465 Least k>=1 such that n^2+kn+1 is prime.

1, 1, 1, 3, 1, 1, 3, 1, 3, 3, 7, 1, 11, 1, 1, 5, 1, 3, 3, 1, 1, 6, 3, 1, 3, 7, 1, 6, 3, 3, 5, 4, 1, 3, 7, 7, 3, 1, 9, 3, 1, 4, 3, 3, 3, 5, 3, 6, 3, 1, 5, 3, 3, 1, 3, 4, 1, 3, 1, 7, 5, 1, 3, 3, 3, 1, 3, 7, 1, 9, 1, 7, 9, 9, 1, 12, 1, 1, 5, 1, 5, 3, 19, 3, 3, 4, 7, 3, 1, 1, 5, 3, 3, 11, 3, 4, 11, 6, 1, 3, 1, 3, 11

Offset

1,4

Links

Table of n, a(n) for n=1..103.

Prog

(PARI) a(n)=if(n<0, 0, k=1; while(isprime(n^2+k*n+1)==0, s++); k)

Crossrefs

Sequence in context: A218825 A035691 A131781 * A226856 A131327 A355899

Adjacent sequences: A082462 A082463 A082464 * A082466 A082467 A082468

Keyword

nonn

Author

Benoit Cloitre, Apr 27 2003

Status

approved