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%I #10 Oct 10 2019 16:16:54
%S 1,1,1,1,1,1,1,2,2,1,1,4,9,4,1,1,8,60,60,8,1,1,16,648,4225,648,16,1,1,
%T 32,12240,2818530,2818530,12240,32,1,1,64,427680,34599304740,
%U 7947815340969,34599304740,427680,64,1,1,128,28641600,14799779785070280
%N Table (read by antidiagonals): t(1,n) = t(m,1) = 1 for all m and n. t(m,n) = (sum{k=1 to m-1} t(k,n)) * (sum{k=1 to n-1} t(m,k)).
%e t(3,4) = (t(1,4)+t(2,4)) * (t(3,1)+t(3,2)+t(3,3)) = (1+4) * (1+2+9) = 60.
%t t[m_, n_] := t[m, n] = If[m == 1 || n == 1, 1,Sum[t[k, n], {k, m - 1}] * Sum[t[m, j], {j, n - 1}]];Flatten@Table[t[d + 1 - j, j], {d, 10}, {j, d}] (* _Ray Chandler_, Nov 19 2006 *)
%Y Cf. A124975.
%K easy,nonn,tabl
%O 1,8
%A _Leroy Quet_, Nov 14 2006
%E Extended by _Ray Chandler_, Nov 19 2006
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