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Numbers k such that k![12]+2 is prime, where k![12] is the twelve-fold multifactorial.
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%I #11 Apr 03 2023 10:36:13

%S 0,1,3,5,9,11,15,21,27,29,39,99,159,213,249,351,443,489,513,563,705,

%T 1059,1599,1733,2361,3699,4263,4451,4479,5141,5751,7355,7461,8525,

%U 8861,18231,19629,23571,41789,76973,86997,93735,98943

%N Numbers k such that k![12]+2 is prime, where k![12] is the twelve-fold multifactorial.

%C a(44) > 10^5.

%C The first 12 primes associated with this sequence: 3, 3, 5, 7, 11, 13, 47, 191, 1217, 2467, 47387.

%H 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The top ten prime numbers: from the unpublished collections of R. Ondrejka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 Ken Davis, <a href="http://mfprimes.free-dc.org">Status of Search for Multifactorial Primes</a>.

%t MultiFactorial[n_, k_] := If[n < 1, 1, n*MultiFactorial[n - k, k]];

%t Select[Range[0, 50000], PrimeQ[MultiFactorial[#, 12] + 2] &]

%Y Cf. A076185, A085158, A094144, A204657.

%K nonn

%O 1,3

%A _Robert Price_, Mar 11 2017

%E a(40)-a(43) from _Robert Price_, Mar 24 2017