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 A283553 #11 Aug 16 2023 20:37:30 %S A283553 0,1,3,5,7,9,11,13,15,19,27,29,31,43,53,75,143,169,185,235,259,363, %T A283553 365,457,493,573,777,1273,1275,1865,3621,4523,5291,5845,7185,10183, %U A283553 12845,15057,16281,17945,18771,22479,27235,28089,31557,39163,45709,46329,52211,77779 %N A283553 Numbers k such that k![4] + 2 is prime, where k![4] = A007662(k) = quadruple factorial. %C A283553 a(51) > 10^5. %C A283553 The first 10 primes associated with this sequence: 3, 3, 5, 7, 23, 47, 233, 587, 3467, 65837. %H A283553 C. Caldwell and H. Dubner (Eds): <a href="https://t5k.org/lists/top_ten/">The top ten prime numbers: from the unpublished collections of R. Ondrejka</a> (May 2001), Table 21 F, p. 75 %H A283553 Ken Davis, <a href="http://mfprimes.free-dc.org">Status of Search for Multifactorial Primes</a>. %t A283553 MultiFactorial[n_, k_] := If[n < 1, 1, n*MultiFactorial[n - k, k]]; %t A283553 Select[Range[0, 50000], PrimeQ[MultiFactorial[#, 4] + 2] &] %t A283553 Select[Range[0,78000],PrimeQ[Times@@Range[#,1,-4]+2]&] (* _Harvey P. Dale_, Aug 16 2023 *) %Y A283553 Cf. A076185, A085158, A094144, A204657. %K A283553 nonn %O A283553 1,3 %A A283553 _Robert Price_, Mar 10 2017 %E A283553 a(49)-a(50) from _Robert Price_, Aug 12 2017