cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A096178 Primes of the form primorial(p)/2+2.

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%I A096178 #10 Dec 27 2019 08:56:52
%S A096178 3,5,17,107,15017,3234846617,100280245067,3710369067407,
%T A096178 307444891294245707,961380175077106319537,
%U A096178 139867498408927468089138080936033904837498617
%N A096178 Primes of the form primorial(p)/2+2.
%C A096178 Primes of the form A070826(n)+2.
%H A096178 Amiram Eldar, <a href="/A096178/b096178.txt">Table of n, a(n) for n = 1..18</a>
%F A096178 a(n) = A070826(A096177(n)) + 2. - _Amiram Eldar_, Dec 26 2019
%e A096178 a(4) = 107 because 107 is a prime of the form primorial(7)/2 + 2 = A070826(4) + 2 = 2*3*5*7/2 + 2.
%o A096178 (PARI) for(n=1,30,p=prod(k=1,n,prime(k))/2+2;if(ispseudoprime(p),print1(p,", "))) \\ _Hugo Pfoertner_, Dec 26 2019
%Y A096178 Cf. A070826, A096177 (primorial(p)/2+2 is prime), A096547 (primorial(p)/2-2 is prime), A067024 (smallest p+2 that has n distinct prime factors), A014545 (primorial primes), A087398.
%K A096178 nonn
%O A096178 1,1
%A A096178 _Hugo Pfoertner_, Jun 27 2004
%E A096178 a(1) inserted by _Amiram Eldar_, Dec 26 2019