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A303739
Numbers k such that 9*k^2 + 3*k + 1 (A082040) is prime.
1
1, 2, 4, 5, 7, 8, 9, 11, 18, 19, 22, 23, 25, 26, 30, 33, 35, 37, 39, 46, 47, 49, 50, 51, 54, 56, 63, 64, 77, 82, 93, 96, 103, 112, 114, 116, 117, 119, 123, 126, 127, 134, 135, 138, 142, 145, 149, 151, 152, 163, 165, 175, 177, 179, 180, 189, 193, 194, 201, 203
OFFSET
1,2
COMMENTS
These are the indices of the primes in A082040.
MAPLE
select(n->isprime(9*n^2+3*n+1), [$0..300]);
PROG
(GAP) Filtered([0..300], n->IsPrime(9*n^2+3*n+1));
CROSSREFS
Cf. A082040, A303740 (corresponding primes).
Sequence in context: A026451 A050106 A345917 * A183544 A219640 A344406
KEYWORD
nonn
AUTHOR
Muniru A Asiru, Jun 01 2018
STATUS
approved