A025189 a(n) = T(n,[ n/2 ]), where T is the array defined in A025177.

1, 1, 1, 2, 7, 11, 35, 56, 189, 302, 1038, 1662, 5797, 9295, 32747, 52572, 186615, 299898, 1070762, 1722236, 6177698, 9943555, 35802935, 57663784, 208279007, 335631410, 1215507450, 1959644390, 7113090285, 11472439905, 41724381765, 67320086700

Offset: 0

Author

Clark Kimberling

Keywords

• nonn

Programs

PARI

g=matrix(33,65);
for(n=0,32,for(k=0,2*n,g[n+1,k+1]=0));
g[1,1]=1;
g[2,1]=1;g[2,2]=0;g[2,3]=1;
g[3,1]=1;g[3,2]=1;g[3,3]=2;g[3,4]=1;g[3,5]=1;
for(n=0,2,k=floor(n/2);print(n," ",k," ",g[n+1,k+1]))
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)