A100923 - OEIS

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A100923

a(n) = 1 iff 6*n+1 and 6*n-1 are both prime numbers (0 otherwise).

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

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Characteristic function of A002822. - Georg Fischer, Aug 04 2021

LINKS

Table of n, a(n) for n=1..105.

EXAMPLE

a(3) = 1 because 6*3-1=17 and 6*3+1=19 are both prime.

a(4) = 0 because 6*4-1=23 is prime and 6*4+1=25 is not prime.

a(20) = 0 because 6*20-1=119 and 6*20+1=121 are both not prime.

MATHEMATICA