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%I
%S 1,1,2,12,24,17280,720,87091200,29030400,1755758592000,3628800,
%T 1525930675524002119680000000,479001600,15033074749223731200000,
%U 151533393472175210496000000,2201737050440244933006930739200000000
%N a(n) = product_{d divides n} (n-d)!.
%e n=6, d(i)< 6 are 1;2;3; a(6)= (6-1)! * (6-2)! * (6-3)! = 17280
%p A135396 := proc(n) local dvs ; dvs := numtheory[divisors](n) minus {n} ; mul( (n-i)!,i=dvs) ; end: seq(A135396(n),n=1..30) ; - _R. J. Mathar_, Feb 19 2008
%t Table[Product[(n - Divisors[n][[i]])!, {i,1,Length[Divisors[n]]}], {n, 1, 20}] - _Stefan Steinerberger_, Feb 19 2008
%Y Cf. A000142.
%K easy,nonn
%O 1,3
%A Ctibor O. ZIZKA (ctibor.zizka(AT)seznam.cz), Feb 17 2008
%E Definition simplified by _Stefan Steinerberger_, Feb 19 2008
%E More terms from _R. J. Mathar_ and _Stefan Steinerberger_, Feb 19 2008
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