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%I
%S 1,1,1,2,1,2,3,1,1,3,6,3,1,3,6,10,2,1,1,2,10,20,10,4,1,4,10,20,35,5,5,
%T 1,1,5,5,35,70,35,5,5,1,5,5,35,70,126,14,7,3,1,1,3,7,14,126,252,126,
%U 28,21,6,1,6,21,28,126,252,462,42,42,14,7,1,1,7,14,42,42,462,924,77,14,21,28
%N Triangle read by rows: C[n,Floor[n/2]]/GCD[C[n,Floor[n/2]],C[n,i], i=0,...n; central binomial coefficient is divided by greatest common divisor of binomial coefficients and corresponding central binomial coefficient.
%e Triangle begins:
%e 1
%e 1 1
%e 2 1 2
%e 3 1 1 3
%e 6 3 1 3 6
%e 10 2 1 1 2 10
%e 20 10 4 1 4 10 20
%e 35 5 5 1 1 5 5 35
%t Table[Table[Binomial[n, Floor[n/2]]/GCD[Binomial[n, j], Binomial[n, Floor[n/2]]], {j, 0, n}], {n, 1, 10}]
%Y Cf. A007318, A001405, A080381.
%K nonn,tabl
%O 1,4
%A Labos E. (labos(AT)ana.sote.hu), Mar 12 2003
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