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Primes of form prime(n)*prime(2*n)+prime(n)+prime(2*n).
3

%I #5 Jul 14 2014 15:22:07

%S 11,31,83,359,1487,4283,4751,5471,7127,12527,41183,66863,71339,85247,

%T 186119,274223,290987,338687,373859,386219,400679,465299,490643,

%U 663407,720791,827147,883739,1096127,1124603

%N Primes of form prime(n)*prime(2*n)+prime(n)+prime(2*n).

%H Harvey P. Dale, <a href="/A072673/b072673.txt">Table of n, a(n) for n = 1..1000</a>

%e A000040(236) = 1487 = 1403+23+61 = 23*61+23+61 = A000040(9)*A000040(18)+A000040(9)+A000040(18), therefore 1487 is a term.

%t p[n_]:=Module[{p1=Prime[n],p2=Prime[2n]},p1*p2+p1+p2]; Select[ Array[ p,200],PrimeQ] (* _Harvey P. Dale_, Jul 14 2014 *)

%Y Cf. A072672, A066938.

%K nonn

%O 1,1

%A _Reinhard Zumkeller_, Jun 30 2002