A096398 Nonnegative numbers k such that 0 = #{ 0 <= i <= k : K(k, i) = -1 } where K(k, i) is the Kronecker symbol.

0, 1, 2, 4, 6, 9, 16, 25, 36, 49, 64, 81, 100, 121, 144, 169, 196, 225, 256, 289, 324, 361, 400, 441, 484, 529, 576, 625, 676, 729, 784, 841, 900, 961, 1024, 1089, 1156, 1225, 1296, 1369, 1444, 1521, 1600, 1681, 1764, 1849, 1936, 2025, 2116, 2209, 2304, 2401

Offset

1,3

Comments

Contains all squares.

These are the indices of the rows of A372728 with nonnegative terms. - Peter Luschny, May 16 2024

Apparently, 2 and 6 are the only nonsquares in the sequence. - Hugo Pfoertner, May 16 2024

Links

Table of n, a(n) for n=1..52.

Mathematica

Reap[For[n = 0, n < 2500, n++, If[NoneTrue[Range[n], KroneckerSymbol[n, #] == -1&], Sow[n]]]][[2, 1]] (* Jean-François Alcover, Nov 18 2016 *)

Prog

(SageMath)
print([n for n in range(999) if 0 == sum(kronecker(n, k) == -1
for k in range(n + 1))])  # Peter Luschny, May 16 2024

Crossrefs

Cf. A000010, A051953, A372728.

Sequence in context: A257655 A318026 A173241 * A110538 A288039 A373639

Adjacent sequences: A096395 A096396 A096397 * A096399 A096400 A096401

Keyword

nonn

Author

Benoit Cloitre, Aug 06 2004

Extensions

0 prepended by Peter Luschny, May 16 2024

Status

approved