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Numbers n such that n!10+1 is prime.
3

%I #27 Nov 12 2019 11:33:52

%S 0,1,2,4,6,10,16,34,46,94,146,156,166,170,194,198,206,308,456,610,614,

%T 734,1288,1512,1558,2066,2090,2122,3434,3560,3642,3896,4294,4534,4962,

%U 5022,5874,8002,9870,11358,11438,13350,15046,16046,20228,25014,30114,35668,38466,46702,48302

%N Numbers n such that n!10+1 is prime.

%C n!10 = product( n-10k, 0 <= k < n/10 ).

%C a(1)-a(51) proved prime by deterministic tests of PFGW. - _Robert Price_, Jun 08 2012

%C a(52) > 50,000. - _Robert Price_, Jun 08 2012

%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/f10p.html">Results for n!10+1.</a>

%H Nathan Russell, <a href="http://groups.yahoo.com/group/primenumbers/message/23995">n!10+2 results</a>, primenumbers group, Jan 2012

%H Nathan Russell, <a href="/A204656/a204656.txt">n!10+2 results</a>, message 23995 in primenumbers Yahoo group, Jan 17, 2012.

%o (PARI) for(n=0,9999,isprime(prod(i=1,(n-2)\10,n-(10*i),n)+1)& print1(n","))

%K nonn,hard

%O 1,3

%A _M. F. Hasler_, Jan 17 2012

%E a(29)-a(51) from _Robert Price_, Jun 08 2012