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.

A090886 Primes in the products of consecutive prime-indexed primes + 2 or A080696(n) + 2.

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%I A090886 #15 Jul 05 2024 08:13:03
%S A090886 5,17,167,14093057717,16192486429745837,
%T A090886 114681479899746991802547357477494807,
%U A090886 12994174855450524638613469509299054674461271855442034674644855689971858721497
%N A090886 Primes in the products of consecutive prime-indexed primes + 2 or A080696(n) + 2.
%C A090886 These numbers, except for the first one, always end in 7.
%C A090886 The next term (a(8)) has 129 digits. - _Harvey P. Dale_, Apr 05 2019
%H A090886 Amiram Eldar, <a href="/A090886/b090886.txt">Table of n, a(n) for n = 1..12</a>
%t A090886 Select[FoldList[Times,Table[Prime[n],{n,Prime[Range[40]]}]]+2,PrimeQ] (* _Harvey P. Dale_, Apr 05 2019 *)
%o A090886 (PARI) piptorial2(n) = { y=1; for(x=1,n, v=prime(prime(x)); y*=v; if(isprime(y+2),print1(y+2",")) ) }
%Y A090886 Cf. A080696, A087400.
%K A090886 nonn
%O A090886 1,1
%A A090886 _Cino Hilliard_, Feb 12 2004