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.
%I A379380 #6 Dec 23 2024 02:14:30 %S A379380 1,2,5,17,103,113,193,277,3671,9419,12671,30809,34439,83833,89227, %T A379380 106103,107101,175303,398903 %N A379380 Prime numbers p such that (2*p)# - p# + 1 is prime, where p# = A034386(p). %e A379380 For p = 17: the product of the primes from 2 to p*2 is 2*3*5*7*11*13*17*19*23*29*31 = 200560490130, and the product of the primes from 2 to p is 2*3*5*7*11*13*17 = 510510. 200560490130 - 510510 + 1 = 200559979621, a prime number. %Y A379380 Cf. A034386, A237443. %K A379380 nonn,hard,more %O A379380 1,2 %A A379380 _Kellen Shenton_, Dec 21 2024