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 A300947 #26 May 28 2018 10:36:17
%S A300947 3,727,20922789928321,403291461126605641811020801,
%T A300947 523022617466601111760007224221719391608832001
%N A300947 Primes of form (2*k)! + k! + 1.
%C A300947 The next term is too large to include.
%F A300947 a(n) = (2*A242487(n))! + A242487(n)! + 1.
%p A300947 select(isprime,[seq(factorial(2*k)+factorial(k)+1,k=0..600)]); # _Muniru A Asiru_, May 27 2018
%o A300947 (PARI) lista(nn) = {for(k=0, nn, if(ispseudoprime(p=(2*k)!+k!+1), print1(p, ", ")));} \\ _Altug Alkan_, Mar 22 2018
%Y A300947 Cf. A088332, A118812, A242487.
%K A300947 nonn
%O A300947 1,1
%A A300947 _Seiichi Manyama_, Mar 22 2018