OFFSET
1,1
COMMENTS
One less than the associated entry in A155723. [ R. J. Mathar, Jan 05 2011]
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..1000
EXAMPLE
Distribution of the terms in the following triangular array:
*
2,7;
5,12,19;
8,17,26,35;
11,22,33,44,55;
14,27,40,53,66,79;
17,32,47,62,77,92,107;
20,37,54,71,88,105,122,139;
23,42,61,80,99,118,137,156,175;
26,47,68,89,110,131,152,173,194,215;
29,52,75,98,121,144,167,190,213,236,259;
32,57,82,107,132,157,182,207,232,257,282,307;
where * marks the decimal values of (2*h*k + k + h - 5) with h >= k >= 1. - Vincenzo Librandi, Jan 16 2013
MATHEMATICA
Select[Range[100], !PrimeQ[2#+11]&] (* Harvey P. Dale, Jul 18 2011 *)
PROG
(Magma) [n: n in [1..120] | not IsPrime(2*n + 11)]; // Vincenzo Librandi, Nov 21 2012
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Dec 18 2008
STATUS
approved