A355450 a(n) = 1 if n is odd and phi(x) = n^2 + 1 has no solutions, otherwise 0.

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

Offset

1

Links

Antti Karttunen, Table of n, a(n) for n = 1..100000

Index entries for characteristic functions

Formula

a(n) = A355451(1 + n^2).

Prog

(PARI)
A355451(n) = (!(n%2) && !istotient(n));
A355450(n) = A355451(1+(n^2));

Crossrefs

Characteristic function of A106571.

Cf. A355451.

Sequence in context: A353464 A144193 A171387 * A333189 A011662 A011665

Adjacent sequences: A355447 A355448 A355449 * A355451 A355452 A355453

Keyword

nonn

Author

Antti Karttunen, Jul 12 2022

Status

approved