A153763 Numbers k >= 0 such that 8*k+9 is not prime.

0, 2, 3, 5, 6, 7, 9, 12, 14, 15, 17, 18, 19, 20, 21, 22, 24, 25, 26, 27, 30, 32, 33, 35, 36, 37, 39, 40, 42, 44, 45, 46, 47, 48, 51, 52, 54, 57, 58, 59, 60, 61, 62, 63, 65, 66, 67, 68, 69, 72, 75, 77, 78, 80, 81, 82, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93

Offset

1,2

Links

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

Example

Distribution of the terms in the following triangular array:
0;
*,2;
*,*,5;
*,*,*,9;
3,*,*,*,14;
*,7,*,*,*,20;
*,*,12,*,*,*,27;
*,*,*,18,*,*,*,35;
6,*,*,*,25,*,*,*,44;
*,12,*,*,*,33,*,*,*,54;
*,*,19,*,*,*,42,*,*,*,65; etc.
where * marks the non-integer values of (2*h*k + k + h - 4)/4 with h >= k >= 1. - Vincenzo Librandi, Jan 14 2013

Mathematica

Select[Range[0, 200], !PrimeQ[8 # + 9] &] (* Vincenzo Librandi, Jan 14 2013 *)

Prog

(Magma) [n: n in [0..150] | not IsPrime(8*n+9)]; // Vincenzo Librandi, Jan 14 2013

Crossrefs

Cf. A153762, A023232.

Sequence in context: A253083 A108130 A195060 * A345982 A050747 A261514

Adjacent sequences: A153760 A153761 A153762 * A153764 A153765 A153766

Keyword

nonn,easy

Author

Vincenzo Librandi, Jan 01 2009

Status

approved