The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation. Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A155722 Numbers k such that 2*k + 9 is prime. 25
 1, 2, 4, 5, 7, 10, 11, 14, 16, 17, 19, 22, 25, 26, 29, 31, 32, 35, 37, 40, 44, 46, 47, 49, 50, 52, 59, 61, 64, 65, 70, 71, 74, 77, 79, 82, 85, 86, 91, 92, 94, 95, 101, 107, 109, 110, 112, 115, 116, 121, 124, 127, 130, 131, 134, 136, 137, 142, 149, 151, 152, 154, 161, 164 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Subsequence of A001651; A011655(a(n)) = 1. - Reinhard Zumkeller, Jul 09 2010 One less than the associated entry in A105760, two less than in A089038, three less than in A067076. - R. J. Mathar, Jan 05 2011 Solutions of the equation (2*n+9)' = 1, where n' is the arithmetic derivative of n. - Paolo P. Lava, Nov 15 2012 LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..1000 MATHEMATICA (Prime[Range[5, 100]] - 9)/2 (* Vladimir Joseph Stephan Orlovsky, Feb 08 2010 *) Select[Range[0, 200], PrimeQ[2 # + 9]&] (* Vincenzo Librandi, Sep 24 2012 *) PROG (MAGMA) [n: n in [0..200] | IsPrime(2*n+9)]; // Vincenzo Librandi, Sep 24 2012 (PARI) is(n)=isprime(2*n+9) \\ Charles R Greathouse IV, Jul 12 2016 (Sage) [n for n in (0..200) if is_prime(2*n+9) ] # G. C. Greubel, May 21 2019 (GAP) Filtered([0..200], k-> IsPrime(2*k+9) ) # G. C. Greubel, May 21 2019 CROSSREFS Cf. A155723, A155724. Numbers h such that 2*h + k is prime: A005097 (k=1), A067076 (k=3), A089038 (k=5), A105760 (k=7), this seq (k=9), A101448 (k=11), A153081 (k=13), A089559 (k=15), A173059 (k=17), A153143 (k=19). Sequence in context: A039672 A014370 A095278 * A049045 A153766 A319301 Adjacent sequences:  A155719 A155720 A155721 * A155723 A155724 A155725 KEYWORD nonn,easy AUTHOR Vincenzo Librandi, Jan 25 2009 EXTENSIONS Edited by N. J. A. Sloane, Jun 23 2010 Definition clarified by Zak Seidov, Jul 11 2014 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 August 5 13:21 EDT 2021. Contains 346469 sequences. (Running on oeis4.)