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 A085149 n!!!!!-1 is prime. 5
 3, 4, 6, 7, 8, 12, 13, 14, 27, 28, 33, 35, 44, 50, 62, 64, 74, 88, 114, 140, 142, 242, 248, 262, 270, 284, 395, 473, 582, 600, 634, 707, 805, 882, 907, 1008, 1152, 1243, 1853, 2340, 2410, 2703, 2793, 3033, 3600, 3925, 4124, 4154, 6185, 6367, 7130, 9104, 9992 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS 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). LINKS Robert Price, Table of n, a(n) for n = 1..63 Ken Davis, Status of Search for Multifactorial Primes. Ken Davis, Results for n!5-1. MATHEMATICA MultiFactorial[n_, k_] := If[n < 1, 1, n*MultiFactorial[n - k, k]]; Select[Range[0, 1000], PrimeQ[MultiFactorial[#, 5] - 1] & ] (* Robert Price, Apr 19 2019 *) CROSSREFS Cf. A085157 (quintuple factorials), A085148. Sequence in context: A285703 A002191 A108348 * A239458 A007370 A322376 Adjacent sequences:  A085146 A085147 A085148 * A085150 A085151 A085152 KEYWORD hard,nonn AUTHOR Hugo Pfoertner, Jun 23 2003 EXTENSIONS More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 03 2008 a(54)-a(63) from Ken Davis link added to b-file by Robert Price, Sep 23 2012 STATUS approved

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Last modified May 12 10:54 EDT 2021. Contains 343821 sequences. (Running on oeis4.)