A177351 Triangle t(n,k)= sum_{m=1..floor(n/2-k)} binomial(n-m-k,m+k), -floor(n/2) <= k <= floor(n/2), read by rows.
0, 0, 2, 1, 0, 3, 2, 0, 5, 5, 4, 1, 0, 8, 8, 7, 3, 0, 13, 13, 13, 12, 7, 1, 0, 21, 21, 21, 20, 14, 4, 0, 34, 34, 34, 34, 33, 26, 11, 1, 0, 55, 55, 55, 55, 54, 46, 25, 5, 0, 89, 89, 89, 89, 89, 88, 79, 51, 16, 1, 0
Offset: 0
Examples
0; 0; 2, 1, 0; 3, 2, 0; 5, 5, 4, 1, 0; 8, 8, 7, 3, 0; 13, 13, 13, 12, 7, 1, 0; 21, 21, 21, 20, 14, 4, 0; 34, 34, 34, 34, 33, 26, 11, 1, 0; 55, 55, 55, 55, 54, 46, 25, 5, 0; 89, 89, 89, 89, 89, 88, 79, 51, 16, 1, 0;
Crossrefs
Cf. A000045
Programs
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Mathematica
w[n_, m_, k_] = Binomial[n - (m + k), m + k]; t[n_, k_] := Sum[w[n, m, k], {m, 1, Floor[n/2 - k]}]; Table[Table[t[n, k], {k, -Floor[n/2], Floor[n/2]}], {n, 0, 10}]; Flatten[%]
Comments