A296212 a(n) = 1 if sigma(n) + 1 is prime, 0 otherwise.

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

Offset

1,1

Comments

Characteristic function of A065512, numbers n such that sigma(n) + 1 is prime.

Links

Antti Karttunen, Table of n, a(n) for n = 1..65537

Index entries for characteristic functions

Formula

a(n) = A010051(1+A000203(n)) = A010051(A088580(n)).

Prog

(Scheme) (define (A296212 n) (A010051 (+ 1 (A000203 n))))

Crossrefs

Cf. A000203, A010051, A065512, A088580, A296092.

Cf. also A296077, A296079, A296211.

Sequence in context: A115955 A106344 A106346 * A189921 A341346 A167371

Adjacent sequences: A296209 A296210 A296211 * A296213 A296214 A296215

Keyword

nonn

Author

Antti Karttunen, Dec 07 2017

Status

approved