A153381 Numbers n such that 11*n+5 is not prime.

1, 2, 3, 4, 5, 7, 8, 9, 10, 11, 13, 14, 15, 17, 18, 19, 20, 21, 22, 23, 25, 26, 27, 29, 30, 31, 32, 33, 35, 37, 38, 39, 40, 41, 43, 44, 45, 46, 47, 48, 49, 50, 51, 53, 55, 56, 57, 59, 60, 61, 62, 63, 65, 66, 67, 68, 69, 70, 71, 73, 74, 75, 76, 77, 79, 80, 81, 83, 85, 86, 87, 88

Offset

1,2

Links

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

Example

Distribution of the even terms in the following triangular array:
*;
*,*;
*,*,4;
2,*,*,*;
*,*,*,*,*;
*,*,*,*,*,*;
*,*,*,*,*,*,20;
*,*,*,*,*,*,*,*,;
*,*,*,*,*,22,*,*,*;
*,*,*,*,*,*,*,32,*,*;
*,10,*,*,*,*,*,*,*,*,*;
*,*,*,20,*,*,*,*,*,*,*,*;
*,*,*,*,*,*,*,*,*,*,56,*,*:
*,*,18,*,*,*,*,*,*,*,*,*,*,76;
8,*,*,*,*,*,*,*,*,*,*,70,*,*,*; etc.
where * marks the non-integer values of (4*h*k + 2*k + 2*h - 4)/11 with h >= k >= 1. - Vincenzo Librandi, Jan 17 2013

Mathematica

Select[Range[0, 200], !PrimeQ[11 # + 5] &] (* Vincenzo Librandi, Jan 13 2013 *)

Prog

(Magma) [n: n in [0..150] | not IsPrime(11*n+5)]; // Vincenzo Librandi, Jan 13 2013

Crossrefs

Cf. A108233.

Sequence in context: A098901 A098767 A333559 * A307750 A356734 A319630

Adjacent sequences: A153378 A153379 A153380 * A153382 A153383 A153384

Keyword

nonn,easy

Author

Vincenzo Librandi, Dec 25 2008

Extensions

Erroneous comment deleted by N. J. A. Sloane, Jun 23 2010

Status

approved