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%I #10 Aug 29 2019 09:13:49
%S 1,1,2,1,3,8,1,4,15,48,1,5,24,105,384,1,6,35,192,945,3840,1,7,48,315,
%T 1920,10395,46080,1,8,63,480,3465,23040,135135,645120,1,9,80,693,5760,
%U 45045,322560,2027025,10321920,1,10,99,960,9009,80640,675675,5160960
%N Triangle of certain double factorials.
%C This is the rectangular array A(3;m,n) := (2*n+m)!!/m!!, m >= 0, n >= 0, read by SW-NE diagonals. For n!! see A006882 (double factorials).
%H W. Lang, <a href="/A092081/a092081.txt">First 9 rows</a>.
%F a(m, n)=(n+m)!!/(m-n)!!, 0<=n<=m, else 0, with 0!! := 1.
%Y Diagonals give: A000165 (double factorials of 2*n), A001147(n+1), A002866, A051577-83.
%Y Columns give: A000012 (powers of 1), A000027 (naturals >=2), A005563, 3*A077415, for n=0..3.
%K nonn,easy,tabl
%O 0,3
%A _Wolfdieter Lang_, Mar 19 2004
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