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A106187
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Sequence array for central binomial numbers A000984.
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3
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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, 3432, 924, 252, 70, 20, 6, 2, 1, 12870, 3432, 924, 252, 70, 20, 6, 2, 1, 48620, 12870, 3432, 924, 252, 70, 20, 6, 2, 1, 184756, 48620, 12870, 3432, 924, 252, 70, 20, 6, 2, 1
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OFFSET
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0,2
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COMMENTS
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The matrix inverse starts
1;
-2,1;
-2,-2,1;
-4,-2,-2,1;
-10,-4,-2,-2,1;
-28,-10,-4,-2,-2,1;
-84,-28,-10,-4,-2,-2,1;
-264,-84,-28,-10,-4,-2,-2,1;
-858,-264,-84,-28,-10,-4,-2,-2,1;
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LINKS
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FORMULA
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Number triangle T(n, k)=binomial(2(n-k), n-k); Riordan array (1/sqrt(1-4x), x).
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EXAMPLE
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Table begins
1;
2,1;
6,2,1;
20,6,2,1;
70,20,6,2,1;
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MAPLE
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binomial(2*(n-k), n-k) ;
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CROSSREFS
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KEYWORD
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AUTHOR
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STATUS
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approved
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