A100923 - OEIS

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

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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