1,3

This is one possible generalization of "the least prime problem" for nk+1 arithmetic progression when n is replaced by n^2, a special difference.

Table of n, a(n) for n=1..94.

Index entries for sequences related to primes in arithmetic progressions

a(40) = 1 because in 1600k + 1 at k = 1, 1601 is the smallest prime; a(61)=46 because in 46*46*k+1 sequence the first prime appears at k=46, it is 171167.

(PARI)

a(n)=k=1; while(!isprime(k*n^2+1), k++); k

vector(100, n, a(n)) \\ Derek Orr, Oct 01 2014

Analogous case is A034693. See also A005574 and A002496.

Sequence in context: A029205 A229340 A072721 * A160598 A107457 A112350

Adjacent sequences: A035089 A035090 A035091 * A035093 A035094 A035095

nonn,easy

Labos Elemer

approved