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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.

A136352 Primorials P for which neither P-1 nor P+1 is prime.

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%I A136352 #17 May 08 2025 22:59:39
%S A136352 510510,9699690,223092870,6469693230,7420738134810,13082761331670030,
%T A136352 614889782588491410,32589158477190044730,1922760350154212639070,
%U A136352 117288381359406970983270,7858321551080267055879090
%N A136352 Primorials P for which neither P-1 nor P+1 is prime.
%C A136352 This sequence is different from A121069 and A002110.
%C A136352 For almost all primes p, p# is in this sequence by Brun's theorem. - _Charles R Greathouse IV_, Sep 14 2015
%H A136352 Charles R Greathouse IV, <a href="/A136352/b136352.txt">Table of n, a(n) for n = 1..350</a>
%F A136352 Compute P = product of the first k primes. If P is neither preceded nor followed by a prime add P to the sequence.
%e A136352 13# = 30030 is preceded by a prime but is not followed by a prime. 17# = 510510 is neither preceded nor followed by a prime.
%t A136352 Select[FoldList[Times, 1, Prime[Range[19]]],!PrimeQ[#+1]&&!PrimeQ[#-1]&] (* _James C. McMahon_, May 08 2025 *)
%Y A136352 Cf. A136349, A136350, A136351, A002110, A121069.
%K A136352 easy,nonn
%O A136352 1,1
%A A136352 _Enoch Haga_, Dec 25 2007
%E A136352 Edited by and more terms from _Charles R Greathouse IV_, Sep 29 2008