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Nonnegative numbers n such that 2*n + 15 is prime.
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%I #37 Feb 04 2024 01:16:52

%S 1,2,4,7,8,11,13,14,16,19,22,23,26,28,29,32,34,37,41,43,44,46,47,49,

%T 56,58,61,62,67,68,71,74,76,79,82,83,88,89,91,92,98,104,106,107,109,

%U 112,113,118,121,124,127,128,131,133,134,139,146,148,149,151,158,161,166

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

%H Vincenzo Librandi, <a href="/A089559/b089559.txt">Table of n, a(n) for n = 1..1000</a>

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

%t (Prime[Range[7,100]]-15)/2 (* _Vladimir Joseph Stephan Orlovsky_, Feb 08 2010 *)

%t Select[Range[0, 200], PrimeQ[2 # + 15] &] (* _Vincenzo Librandi_, Apr 28 2014 *)

%o (Magma) [n: n in [0..200] | IsPrime(2*n+15)]; // _Vincenzo Librandi_, Apr 28 2014

%o (PARI) is(n)=isprime(2*n+15) \\ _Charles R Greathouse IV_, Apr 28 2015

%o (Sage) [n for n in (0..200) if is_prime(2*n+15) ] # _G. C. Greubel_, May 22 2019

%o (GAP) Filtered([0..200], k-> IsPrime(2*k+15) ) # _G. C. Greubel_, May 22 2019

%Y Cf. A086303.

%Y 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).

%Y 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).

%K easy,nonn

%O 1,2

%A _Ray Chandler_, Nov 29 2003

%E Definition clarified by _Zak Seidov_, Jul 11 2014