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
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Jan 01 2009
STATUS
approved