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Primes P of the form P=(j*P(i)#)/2 - 2 such that P+4 is the next prime, where j is odd, 0 < j < P(i+1), P(i) = i-th prime, P(i)# = i-th primorial (A002110).
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%I #5 Oct 12 2013 15:14:05

%S 7,13,43,103,313,3463,15013,195193,225223,765763,4339333,3011753743,

%T 9704539843,100280245063,2707566616753,124286232650865283,

%U 150451755314205343,10760571195298599673,211829530101735290743

%N Primes P of the form P=(j*P(i)#)/2 - 2 such that P+4 is the next prime, where j is odd, 0 < j < P(i+1), P(i) = i-th prime, P(i)# = i-th primorial (A002110).

%C I think I have a proof that the sequence is infinite.

%e (27*2*3*5*7*11*13*17*19*23)/2 - 2 = 3011753743 and (27*2*3*5*7*11*13*17*19*23)/2 + 2 = 3011753747 are gap 4 primes, so j=27, i=9, P(i)=23.

%Y Cf. A087821, A087822, etc.

%K nonn

%O 0,1

%A _Pierre CAMI_, Oct 06 2003

%E More terms from _Ray Chandler_, Oct 19 2003