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.

A093622 Largest prime of the form n!/k!-1.

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%I A093622 #6 Jul 09 2023 09:27:30
%S A093622 5,23,59,719,5039,6719,181439,5039,6652799,479001599,154439,
%T A093622 87178291199,54486431999,3487131647999,59281238015999,
%U A093622 1067062284287999,1013709170073599,405483668029439999,39070079,180503769599
%N A093622 Largest prime of the form n!/k!-1.
%H A093622 Dario Alpern, <a href="https://www.alpertron.com.ar/ECM.HTM">Factorization using the Elliptic Curve Method.</a>
%e A093622 a(5) =59 because 5!/1!-1=119=7*17 is composite, whereas 5!/2!-1=59 is prime.
%o A093622 ECM, see link.
%Y A093622 Cf. A093623 smallest k>0 such that n!/k!-1 is prime, A055490 primes of form n!-1, A093437 largest prime of the form n!/k!+1.
%K A093622 nonn
%O A093622 3,1
%A A093622 _Hugo Pfoertner_, Apr 06 2004