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%I #27 Aug 19 2021 12:53:53
%S 0,1,2,4,6,10,11,12,13,14,16,17,18,19,21,24,25,32,40,43,48,49,50,57,
%T 60,71,73,82,83,86,97,105,114,121,142,147,159,168,195,205,210,212,233,
%U 262,288,289,300,309,316,323,356,403,447,505,514,553,735,739,777
%N Numbers n such that n!9+1 is prime.
%C n!9 = A114806(n).
%C a(107) > 50000. - _Robert Price_, Jun 18 2012
%C a(1)-a(106) verified prime by deterministic test of PFGW. - _Robert Price_, Jun 18 2012
%H Robert Price, <a href="/A204660/b204660.txt">Table of n, a(n) for n = 1..106</a>
%H Ken Davis, <a href="http://mfprimes.free-dc.org">Status of Search for Multifactorial Primes</a>.
%H Ken Davis, <a href="http://mfprimes.free-dc.org/mfdata/f09p.html">Results for n!9+1.</a>
%t MultiFactorial[n_, k_] := If[n < 1, 1, n*MultiFactorial[n - k, k]];
%t Select[Range[0, 1000], PrimeQ[MultiFactorial[#, 9] + 1] & ] (* _Robert Price_, Apr 19 2019 *)
%t Select[Range[0,800],PrimeQ[Times@@Range[#,1,-9]+1]&] (* _Harvey P. Dale_, Aug 19 2021 *)
%o (PARI) for(n=0,9999,isprime(prod(i=0,(n-2)\9,n-9*i)+1)& print1(n","))
%Y Cf. A204657, A204658, A204659, A204661, A204662, A204663, A204664, A156165, A156167, A085150, A085148, A085146, A037083, A080778, A002981.
%K nonn,hard
%O 1,3
%A _M. F. Hasler_, Jan 17 2012
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