A164622 - OEIS

%I #3 Mar 31 2012 12:38:26

%S 151,463,571,631,643,991,1063,1171,1831,2083,2311,4951,5023,6211,6703,

%T 6763,7723,7951,9043,11383,12163,12391,13183,14851,15031,17431,19231,

%U 19543,20143,22051,23143,25951,26371,27283,28351,29131,30643,32803

%N Primes p such that p*floor(p/2) - 4 and p*floor(p/2) + 4 are prime numbers.

%C 151*75-4=11321 (prime), 151*75+4=11329 (prime), ..

%t lst={};Do[p=Prime[n];If[PrimeQ[p*Floor[p/2]-4]&&PrimeQ[p*Floor[p/2]+4],AppendTo[lst,p]],{n,8!}];lst

%Y Subsequence of A068229. Cf. A008846, A020882, A068229, A086519, A158708, A164620, A164621

%K nonn

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, Aug 17 2009

%E Edited by _Charles R Greathouse IV_, Nov 02 2009