A374016 a(n) = 1 if n is a fourth power, else 0.

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

Offset

0

Links

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

Index entries for characteristic functions

Index entries for sequences computed from exponents in factorization of n

Formula

G.f.: Sum_{k>=0} x^(k^4).

Mathematica

Array[Boole[IntegerQ[#^(1/4)]] &, 100, 0] (* Paolo Xausa, Jul 02 2024 *)

Prog

(PARI) a(n) = ispower(n, 4);
(PARI) my(N=110, x='x+O('x^N)); Vec(sum(k=0, sqrtnint(N, 4), x^k^4))

Crossrefs

Characteristic function of A000583.

Cf. A010052, A010057.

Sequence in context: A016422 A016399 A016383 * A279485 A298859 A216280

Adjacent sequences: A374011 A374012 A374014 * A374017 A374018 A374019

Keyword

nonn,easy,changed

Author

Seiichi Manyama, Jun 25 2024

Status

approved