A147969 Smallest prime p modulo which numbers 1,2,...,n are quadratic residues.

2, 7, 23, 23, 71, 71, 311, 311, 311, 311, 479, 479, 1559, 1559, 1559, 1559, 5711, 5711, 10559, 10559, 10559, 10559, 18191, 18191, 18191, 18191, 18191, 18191, 31391, 31391, 366791, 366791, 366791, 366791, 366791, 366791, 366791, 366791, 366791

Offset: 1

Author

Max Alekseyev, Nov 18 2008

Keywords

• nonn

Comments

The same primes without repetitions are listed in A147970.

Links

• Charles R Greathouse IV, Table of n, a(n) for n = 1..100

Crossrefs

Cf. A000229, A002223, A002224, A045535, A053760, A133435, A147970, A147971.

Programs

PARI

a(n)=forprime(p=2,default(primelimit),forprime(i=2,n, if(kronecker(i,p)<1,next(2)));return(p)) \\ Charles R Greathouse IV, Apr 06 2012