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%I #5 Apr 08 2013 05:18:00
%S 1,2,1,6,2,1,20,6,2,1,70,20,6,2,1,252,70,20,6,2,1,924,252,70,20,6,2,1,
%T 3432,924,252,70,20,6,2,1,12870,3432,924,252,70,20,6,2,1,48620,12870,
%U 3432,924,252,70,20,6,2,1,184756,48620,12870,3432,924,252,70,20,6,2,1
%N Sequence array for central binomial numbers A000984.
%C Row sums are A006134. Diagonal sums are A106188.
%C The matrix inverse starts
%C 1;
%C -2,1;
%C -2,-2,1;
%C -4,-2,-2,1;
%C -10,-4,-2,-2,1;
%C -28,-10,-4,-2,-2,1;
%C -84,-28,-10,-4,-2,-2,1;
%C -264,-84,-28,-10,-4,-2,-2,1;
%C -858,-264,-84,-28,-10,-4,-2,-2,1;
%C apparently related to A002420. - _R. J. Mathar_, Apr 08 2013
%F Number triangle T(n, k)=binomial(2(n-k), n-k); Riordan array (1/sqrt(1-4x), x).
%e Table begins
%e 1;
%e 2,1;
%e 6,2,1;
%e 20,6,2,1;
%e 70,20,6,2,1;
%p A106187 := proc(n,k)
%p binomial(2*(n-k),n-k) ;
%p end proc: # _R. J. Mathar_, Apr 08 2013
%K easy,nonn,tabl
%O 0,2
%A _Paul Barry_, Apr 24 2005
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