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 A296212 a(n) = 1 if sigma(n) + 1 is prime, 0 otherwise. 3
 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 (list; graph; refs; listen; history; text; internal format)
 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 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 A167371 A127241 Adjacent sequences:  A296209 A296210 A296211 * A296213 A296214 A296215 KEYWORD nonn AUTHOR Antti Karttunen, Dec 07 2017 STATUS approved

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Last modified September 22 12:19 EDT 2019. Contains 327307 sequences. (Running on oeis4.)