

A140366


a(n) = isprime(6n1) + 2*isprime(6n5), where isprime = A010051.


0



1, 3, 3, 3, 1, 2, 3, 3, 1, 1, 2, 3, 2, 3, 1, 0, 3, 3, 3, 0, 0, 3, 1, 2, 1, 2, 2, 3, 1, 1, 2, 1, 3, 2, 0, 2, 0, 3, 3, 1, 2, 1, 1, 1, 1, 2, 3, 2, 1, 0, 0, 3, 3, 0, 0, 2, 2, 1, 3, 1
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OFFSET

1,2


COMMENTS

The idea is to consider 2bit words, where the least resp. most significant bit correspond to primality of the respective member in the couple (6n1,6n5). (It might have been more natural to inverse the correspondences, i.e. to associate the LSB to the smaller number of the pair.)  M. F. Hasler, Jun 16 2008


LINKS

Table of n, a(n) for n=1..60.


PROG

(PARI) a(n)=isprime(6*n5)<<1+isprime(6*n1) \\ M. F. Hasler, Jun 16 2008


CROSSREFS

Cf. A002476, A007528.
Sequence in context: A172364 A323596 A323375 * A167817 A153401 A181520
Adjacent sequences: A140363 A140364 A140365 * A140367 A140368 A140369


KEYWORD

nonn


AUTHOR

JuriStepan Gerasimov, Jun 10 2008


EXTENSIONS

Edited by M. F. Hasler, Jun 16 2008


STATUS

approved



