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Greater of two consecutive primes, p < q, such that p*q-p+q is prime.
3

%I #8 Nov 24 2019 09:58:40

%S 3,5,7,29,37,67,89,97,151,181,241,257,269,271,359,373,421,439,457,509,

%T 563,571,577,593,659,709,739,769,853,947,991,997,1117,1129,1193,1201,

%U 1291,1297,1321,1399,1423,1471,1499,1511,1579,1627,1657,1721,1753,1907

%N Greater of two consecutive primes, p < q, such that p*q-p+q is prime.

%C 3*5+2=17, 7*5+2=37, 23*29+6=673,...

%H Harvey P. Dale, <a href="/A154551/b154551.txt">Table of n, a(n) for n = 1..1000</a>

%t lst={};Do[pp=Prime[n-1];p=Prime[n];d=p-pp;If[PrimeQ[pp*p+d],AppendTo[lst,p]],{n,2,7!}];lst

%t Select[Partition[Prime[Range[300]],2,1],PrimeQ[Times@@#-#[[1]]+#[[2]]]&][[All,2]] (* _Harvey P. Dale_, Sep 13 2018 *)

%Y Cf. A138111, A138170, A154550

%K nonn

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, Jan 11 2009

%E Edited by _Omar E. Pol_, Jan 12 2009