A355449 a(n) = 1 if n^2 + 2 is prime, 0 otherwise.

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

Offset

0

Links

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

Index entries for characteristic functions

Formula

a(n) = A010051(A059100(n)).

Mathematica

a[n_] := If[PrimeQ[n^2 + 2], 1, 0]; Array[a, 100, 0] (* Amiram Eldar, Jul 12 2022 *)

Prog

(PARI) A355449(n) = isprime(2+(n^2));
(Python)
from sympy import isprime
def A355449(n): return int(isprime(n**2+2)) # Chai Wah Wu, Jul 13 2022

Crossrefs

Characteristic function of A067201.

Cf. A010051, A059100.

Cf. also A295405.

Sequence in context: A267537 A329670 A183919 * A058840 A266155 A262683

Adjacent sequences: A355446 A355447 A355448 * A355450 A355451 A355452

Keyword

nonn

Author

Antti Karttunen, Jul 12 2022

Status

approved