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.

A133834 Numbers k such that primorial(k)^4 + 1 is prime.

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%I A133834 #6 Apr 13 2025 07:55:48
%S A133834 0,1,2,4,23,76,339,1282
%N A133834 Numbers k such that primorial(k)^4 + 1 is prime.
%C A133834 Seven terms found and primes proved by PrimeForm ([N-1, Brillhart-Lehmer-Selfridge]). p(1282)#^4 + 1 has 18042 decimal digits. There are no more terms <= 2810.
%C A133834 a(9) > 5000. - _Michael S. Branicky_, Apr 13 2025
%e A133834 As primorial(2)^4 + 1 = (3*2)^4 + 1 = 1297 is prime, 2 is a term.
%Y A133834 Cf. A002110, A092061.
%K A133834 nonn,hard,more
%O A133834 1,3
%A A133834 _Rick L. Shepherd_, Sep 26 2007
%E A133834 a(1) = 0 inserted by _Michael S. Branicky_, Apr 13 2025