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Primes of the form k!9+1, where k!9 is the nonuple factorial number (A114806).
1

%I #5 Jun 08 2017 18:19:17

%S 2,3,5,7,11,23,37,53,71,113,137,163,191,757,2161,2801,51521,1418561,

%T 4093601,42456961,69509441,105616001,2420046721,9160905601,

%U 1270453824641,2326680294401,190787784140801,509498986796801,2805949277824001,612940220628736001

%N Primes of the form k!9+1, where k!9 is the nonuple factorial number (A114806).

%H Robert Price, <a href="/A288371/b288371.txt">Table of n, a(n) for n = 1..55</a>

%H OpenPFGW Project, <a href="http://sourceforge.net/projects/openpfgw/">Primality Tester</a>

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

%t Select[Table[MultiFactorial[i, 9] + 1, {i, 0, 100}], PrimeQ[#]&]

%Y Cf. A204660.

%K nonn

%O 1,1

%A _Robert Price_, Jun 08 2017