A153383 Numbers n such that 12*n+1 is not prime.

0, 2, 4, 7, 10, 11, 12, 14, 17, 18, 21, 22, 24, 25, 27, 30, 32, 37, 39, 40, 41, 42, 43, 44, 46, 47, 49, 52, 53, 54, 57, 58, 60, 62, 65, 66, 67, 68, 70, 72, 74, 75, 76, 77, 79, 80, 81, 82, 87, 88, 90, 92, 95, 97, 98, 99, 102, 105, 106, 107, 109, 111, 112, 113, 114

Offset: 1

Author

Vincenzo Librandi, Dec 25 2008

Keywords

• nonn
• easy

Comments

Complement of A110801 (12*n+1 is prime). [Klaus Brockhaus, Jan 02 2009]

Examples

			Triangle begins:
*;
*,2;
*,*,4;
*,*,*,*;
*,*,*,*,10;
*,*,*,*,*,14;
*,*,*,*,*,*,*:
*,7,*,*,*,*,*,24;
*,*,11,*,*,*,*,*,30;
where * marks the non-integer values of (2*h*k + k + h)/6 with h >= k >= 1.- _Vincenzo Librandi_, Jan 13 2013
		

Links

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

Crossrefs

Cf. A110801.

Programs

Magma

[ n: n in [0..120] | not IsPrime(12*n+1) ]; // Klaus Brockhaus, Jan 02 2009

Mathematica

Select[Range[0, 200], !PrimeQ[12*# + 1] &] (* Vincenzo Librandi, Jan 13 2013 *)

Extensions

More terms from Klaus Brockhaus, Jan 02 2009

0 added by Arkadiusz Wesolowski, Aug 03 2011