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 A085149 #24 May 31 2024 19:56:47 %S A085149 3,4,6,7,8,12,13,14,27,28,33,35,44,50,62,64,74,88,114,140,142,242,248, %T A085149 262,270,284,395,473,582,600,634,707,805,882,907,1008,1152,1243,1853, %U A085149 2340,2410,2703,2793,3033,3600,3925,4124,4154,6185,6367,7130,9104,9992 %N A085149 Numbers k such that k!!!!! - 1 is prime. %C A085149 The search for multifactorial primes started by Ray Ballinger is now continued by a team of volunteers on the website of Ken Davis (see link). %H A085149 Robert Price, <a href="/A085149/b085149.txt">Table of n, a(n) for n = 1..63</a> %H A085149 Ken Davis, <a href="http://mfprimes.free-dc.org">Status of Search for Multifactorial Primes</a>. %H A085149 Ken Davis, <a href="http://mfprimes.free-dc.org/mfdata/f05m.html">Results for n!5-1</a>. %t A085149 MultiFactorial[n_, k_] := If[n < 1, 1, n*MultiFactorial[n - k, k]]; %t A085149 Select[Range[0, 1000], PrimeQ[MultiFactorial[#, 5] - 1] & ] (* _Robert Price_, Apr 19 2019 *) %Y A085149 Cf. A085157 (quintuple factorials), A085148. %K A085149 hard,nonn %O A085149 1,1 %A A085149 _Hugo Pfoertner_, Jun 23 2003 %E A085149 More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 03 2008 %E A085149 a(54)-a(63) from Ken Davis link added to b-file by _Robert Price_, Sep 23 2012