A089559 Nonnegative numbers n such that 2*n + 15 is prime.

1, 2, 4, 7, 8, 11, 13, 14, 16, 19, 22, 23, 26, 28, 29, 32, 34, 37, 41, 43, 44, 46, 47, 49, 56, 58, 61, 62, 67, 68, 71, 74, 76, 79, 82, 83, 88, 89, 91, 92, 98, 104, 106, 107, 109, 112, 113, 118, 121, 124, 127, 128, 131, 133, 134, 139, 146, 148, 149, 151, 158, 161, 166

Offset: 1

Author

Ray Chandler, Nov 29 2003

Keywords

• easy
• nonn

Links

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

Crossrefs

Cf. A086303.

Numbers n such that 2n+k is prime: A005097 (k=1), A067076 (k=3), A089038 (k=5), A105760 (k=7), A155722 (k=9), A101448 (k=11), A153081 (k=13), this seq (k=15), A173059 (k=17), A153143 (k=19).

Numbers n such that 2n-k is prime: A006254 (k=1), A098090 (k=3), A089253 (k=5), A089192 (k=7), A097069 (k=9), A097338 (k=11), A097363 (k=13), A097480 (k=15), A098605 (k=17), A097932 (k=19).

Programs

GAP

Filtered([0..200], k-> IsPrime(2*k+15) ); # G. C. Greubel, May 22 2019

Magma

[n: n in [0..200] |  IsPrime(2*n+15)]; // Vincenzo Librandi, Apr 28 2014

Mathematica

(Prime[Range[7,100]]-15)/2 (* Vladimir Joseph Stephan Orlovsky, Feb 08 2010 *)
Select[Range[0, 200], PrimeQ[2 # + 15] &] (* Vincenzo Librandi, Apr 28 2014 *)

PARI

is(n)=isprime(2*n+15) \\ Charles R Greathouse IV, Apr 28 2015

Sage

[n for n in (0..200) if is_prime(2*n+15) ] # G. C. Greubel, May 22 2019

Formula

a(n) = A086303(n)/2.

Extensions

Definition clarified by Zak Seidov, Jul 11 2014