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Clark Kimberling (ck6(AT)evansville.edu)
Contribution from _Michael B. Porter (michael_b_porter(AT)yahoo.com), _, Feb 02 2010: (Start)
Contribution from Michael B. Porter (michael_b_porter(AT)yahoo.com), Feb 02 2010: (Start)
(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)
nonn,new
nonn
nonn,new
nonn
Clark Kimberling (ck6@cedar.(AT)evansville.edu)
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
0,4
nonn
Clark Kimberling (ck6@cedar.evansville.edu)
approved