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A025189
a(n) = T(n,[ n/2 ]), where T is the array defined in A025177.
0
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
0,4
PROG
Contribution from Michael B. Porter, 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)
CROSSREFS
Sequence in context: A371201 A026133 A026162 * A297348 A023250 A106013
KEYWORD
nonn
STATUS
approved