A228373 Numbers n such that 27*n + 1 is not prime.

0, 1, 2, 3, 5, 7, 8, 9, 11, 12, 13, 15, 17, 19, 21, 22, 23, 24, 25, 26, 27, 29, 31, 32, 33, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 49, 50, 51, 52, 53, 55, 56, 57, 59, 61, 62, 63, 64, 65, 67, 68, 69, 70, 71, 72, 73, 75, 77, 78, 79, 81, 82, 83, 85, 86, 87, 89, 90

Offset

1,3

Comments

Complement of A224467.

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Mathematica

Select[Range[0, 120], ! PrimeQ[27 # + 1]&]

Prog

(Magma) [n: n in [0..120] | not IsPrime(27*n + 1)];

Crossrefs

Cf. A224467.

Sequence in context: A053661 A171944 A134623 * A156271 A186513 A350799

Adjacent sequences: A228370 A228371 A228372 * A228374 A228375 A228376

Keyword

nonn,less,easy

Author

Vincenzo Librandi, Aug 21 2013

Status

approved