A227194 Natural numbers for which all sums Sum_{i=1..u} K(i/n) (with u ranging from 1 to n) are nonnegative, where K(i/n) is Kronecker symbol of i and n.

1, 2, 3, 4, 6, 7, 9, 10, 11, 12, 14, 15, 16, 23, 24, 25, 26, 27, 30, 31, 34, 35, 36, 38, 39, 42, 44, 47, 48, 49, 54, 55, 56, 58, 59, 62, 63, 64, 66, 71, 74, 75, 76, 79, 81, 82, 83, 86, 87, 94, 95, 96, 100, 103, 106, 108, 110, 111, 114, 119, 120, 121, 130, 131

Offset: 1

Author

Antti Karttunen, Jul 06 2013

Keywords

• nonn

Crossrefs

Subsets: A095100, A095102 (gives the prime terms). Cf. A227196-A227198.

Programs

PARI

firstdiving(n) = {s=0;for(k=1,n,s=s+kronecker(k,n);if(s<0,return(k)));return(0)}
for(n=1,500,if((0==firstdiving(n)),print1(n,", ")))