This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A153044 Numbers n such that 2*n-9 is not a prime. 3
 5, 9, 12, 15, 17, 18, 21, 22, 24, 27, 29, 30, 32, 33, 36, 37, 39, 42, 43, 45, 47, 48, 50, 51, 52, 54, 57, 60, 62, 63, 64, 65, 66, 67, 69, 71, 72, 75, 76, 77, 78, 81, 82, 84, 85, 87, 89, 90, 92, 93, 96, 97, 98, 99, 102, 105, 106, 107, 108, 109, 111, 112, 113, 114, 115, 117, 120 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS One more than the associated entry in A153039. - R. J. Mathar, Jan 05 2011 The terms after a(1) are the values of 2*h*k + k + h + 5, where h and k are positive integers. - Vincenzo Librandi, Jan 19 2013 LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..1000 MATHEMATICA Select[Range[150], !PrimeQ[2#-9]&]  (* Harvey P. Dale, Mar 05 2011 *) PROG (MAGMA) [n: n in [5..121] | not IsPrime(2*n-9)]; // Bruno Berselli, Mar 05 2011 CROSSREFS Cf. A097069, A153039. Sequence in context: A314612 A314613 A102183 * A106635 A314614 A182617 Adjacent sequences:  A153041 A153042 A153043 * A153045 A153046 A153047 KEYWORD nonn,easy AUTHOR Vincenzo Librandi, Dec 17 2008 EXTENSIONS Corrected and extended by N. J. A. Sloane, May 29 2010 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified October 14 12:31 EDT 2019. Contains 328006 sequences. (Running on oeis4.)