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a(n) = least integer of the form (n!-1)(n!-2)...(n!-k)/n!.
1

%I #7 Aug 08 2015 22:29:07

%S 10,8855,182637273,187913191983517,16299312030218924938187,

%T 173083581780047419995380839040497,

%U 300642522445723721070400405660702004585922575,109109034687569422667248530075550555291614316919209445960161,10269669381215922304236773275682334781908421087118493054965910074350106387039

%N a(n) = least integer of the form (n!-1)(n!-2)...(n!-k)/n!.

%C k <= n. Subsidiary sequence: n such that k < n.

%e a(3) = 5*4*3/6 =10. a(4) = 23*22*21*20/4! = 8855.

%p A109893 := proc(n) local k ; for k from 1 to n do if mul( n!-i,i=1..k) mod ( n! ) = 0 then RETURN( mul(n!-i,i=1..k)/n!) ; fi ; od: end: seq(A109893(n),n=3..12) ; # _R. J. Mathar_, Feb 13 2008

%Y Cf. A109892.

%K nonn

%O 3,1

%A _Amarnath Murthy_, Jul 13 2005

%E Corrected and extended by _R. J. Mathar_, Feb 13 2008