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%I #2 Mar 30 2012 18:59:15
%S 1,3,1,3,3,1,1,3,3,1,0,1,3,3,1,0,0,1,3,3,1,0,0,0,1,3,3,1,0,0,0,0,1,3,
%T 3,1,0,0,0,0,0,1,3,3,1,0,0,0,0,0,0,1,3,3,1,0,0,0,0,0,0,0,1
%N Riordan array ((1+x)^3,x).
%C Row sums are A115291. Diagonal sums are A113311. Inverse is A122432. Sequence array for C(3,n).
%F Number triangle T(n,k)=C(3,n-k)
%e Triangle begins
%e 1,
%e 3,1,
%e 3,3,1,
%e 1,3,3,1,
%e 0,1,3,3,1,
%e 0,0,1,3,3,1,
%e 0,0,0,1,3,3,1,
%e 0,0,0,0,1,3,3,1
%K easy,nonn,tabl
%O 0,2
%A _Paul Barry_, Sep 04 2006