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%I #11 Oct 27 2019 05:17:00
%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: T(n,k) = C(n,floor(n/2))/gcd(C(n,floor(n/2)),C(n,k)), k=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 Elemer_, Mar 12 2003
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