A326615 a(n) is the smallest prime p such that Sum_{primes q <= p} Kronecker(n,q) > 0, or 0 if no such prime exists.

2, 11100143, 61981, 3, 2082927221, 5, 2, 11100143, 2, 3, 577, 61463, 2083, 11, 2, 3, 2, 11100121, 5, 2082927199, 1217, 3, 2, 5, 2, 17, 61981, 3, 719, 7, 2, 11100143, 2, 3, 23, 5, 11, 31, 2, 3, 2, 13, 17, 7, 2082927199, 3, 2, 61463, 2, 11100121, 7, 3, 17, 5, 2, 11, 2, 3, 31, 7, 5, 41, 2, 3

Offset

1,1

Links

Richard N. Smith, Table of n, a(n) for n = 1..4096

Formula

a(A003658(n)) = A306499(n).

a(n) = 2 iff n == 1 or 7 mod 8 (see A047522).

a(n) = 3 iff n == 4 mod 6 (see A016957).

Prog

(PARI) a(n) = my(i=0); forprime(p=2, oo, i+=kronecker(n, p); if(i>0, return(p))) \\ after Jianing Song in A306499

Crossrefs

Cf. A306499, A306500.

Sequence in context: A324440 A121390 A170997 * A259407 A157992 A322145

Adjacent sequences: A326612 A326613 A326614 * A326616 A326617 A326618

Keyword

nonn

Author

Richard N. Smith, Jul 15 2019

Status

approved