

A153276


Numbers n >= 0 such that 5*n+6 is not prime.


1



0, 2, 3, 4, 6, 8, 9, 10, 12, 14, 15, 16, 17, 18, 20, 21, 22, 23, 24, 26, 27, 28, 30, 31, 32, 33, 34, 36, 38, 39, 40, 42, 43, 44, 45, 46, 48, 50, 51, 52, 54, 56, 57, 58, 59, 60, 62, 63, 64, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 80, 81, 82, 84, 86, 87, 88, 89, 90
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,2


COMMENTS

The odd terms are the integer values of (4*h*k + 2*k + 2*h  5)/5, where h and k are positive integers.  Vincenzo Librandi, Jan 17 2013
The corresponding composite numbers are 6, 16, 21, 26, 36, 46, 51, 56, 66, 76, 81, 86, 91, 96, 106, 111, 116, 121, ...  Michael B. Porter, Jan 17 2013


LINKS

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


MATHEMATICA

Select[Range[0, 200], !PrimeQ[5 # + 6]&] (* Vincenzo Librandi, Jan 12 2013 *)


PROG

(MAGMA) [n: n in [0..150]  not IsPrime(5*n + 6)]; // Vincenzo Librandi, Jan 12 2013


CROSSREFS

Cf. A081759.
Sequence in context: A321473 A125292 A101513 * A298866 A108408 A173905
Adjacent sequences: A153273 A153274 A153275 * A153277 A153278 A153279


KEYWORD

nonn,easy


AUTHOR

Vincenzo Librandi, Dec 22 2008


EXTENSIONS

Erroneous comment deleted by N. J. A. Sloane, Jun 23 2010
Corrected by Jon E. Schoenfield, Jun 24 2010


STATUS

approved



