A025189 - OEIS

%I #5 Mar 30 2012 18:56:01

%S 1,1,1,2,7,11,35,56,189,302,1038,1662,5797,9295,32747,52572,186615,

%T 299898,1070762,1722236,6177698,9943555,35802935,57663784,208279007,

%U 335631410,1215507450,1959644390,7113090285,11472439905,41724381765,67320086700

%N a(n) = T(n,[ n/2 ]), where T is the array defined in A025177.

%o Contribution from _Michael B. Porter_, Feb 02 2010: (Start)

%o (PARI) g=matrix(33,65);

%o for(n=0,32,for(k=0,2*n,g[n+1,k+1]=0));

%o g[1,1]=1;

%o g[2,1]=1;g[2,2]=0;g[2,3]=1;

%o g[3,1]=1;g[3,2]=1;g[3,3]=2;g[3,4]=1;g[3,5]=1;

%o for(n=0,2,k=floor(n/2);print(n," ",k," ",g[n+1,k+1]))

%o for(n=3,32,g[n+1,1]=1;print(n," 1 1");g[n+1,2]=n-1;print(n," 2 ",n-1);for(k=2,2*n,g[n+1,k+1]=g[n,k-1]+g[n,k]+g[n,k+1];if(k==floor(n/2),print(n," ",k," ",g[n+1,k+1])))) (End)

%K nonn

%O 0,4

%A _Clark Kimberling_