A379952 a(n) = 1 if n is an odd number or a perfect square, otherwise 0.

1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1

Offset

0

Links

Antti Karttunen, Table of n, a(n) for n = 0..100000

Index entries for characteristic functions.

Mathematica

A379952[n_] := Boole[OddQ[n] || IntegerQ[Sqrt[n]]]; Array[A379952, 100, 0] (* Paolo Xausa, Jan 15 2025 *)

Prog

(PARI) A379952(n) = ((n%2) || issquare(n));

Crossrefs

After the initial a(0)=1, the characteristic function of A128201, union of positive squares and the odd numbers.

Cf. also A323158.

Sequence in context: A249066 A176178 A267778 * A285384 A165728 A337966

Adjacent sequences: A379949 A379950 A379951 * A379953 A379954 A379955

Keyword

nonn,easy,changed

Author

Antti Karttunen, Jan 15 2025

Status

approved