

A295405


a(n) = 1 if n^2+1 is prime, 0 otherwise.


1



1, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0
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OFFSET

1


COMMENTS

It is conjectured that n^2+1 is prime infinitely often.


LINKS

Simon Plouffe, Table of n, a(n) for n =1.. 10000


FORMULA

a(n) = A010051(A002522(n)).  Robert Israel, Nov 22 2017


EXAMPLE

With n=1, a(1) = 2, n=2, a(2) = 5, a(3) = 0 since 10 is not prime.


MAPLE

seq(`if`(isprime(n^2+1), 1, 0), n=1..100); # Robert Israel, Nov 22 2017


PROG

(PARI) a(n)=if(isprime(n^2+1), 1)
for (n = 1, 1000, print(a(n)))


CROSSREFS

Cf. A002496, A002522, A010051.
Sequence in context: A147612 A323509 A197183 * A267001 A141735 A322585
Adjacent sequences: A295402 A295403 A295404 * A295406 A295407 A295408


KEYWORD

nonn


AUTHOR

Simon Plouffe, Nov 22 2017


STATUS

approved



