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A193894
Mirror of the triangle A193893.
2
1, 4, 2, 44, 28, 12, 210, 150, 90, 36, 680, 520, 360, 208, 80, 1750, 1400, 1050, 710, 400, 150, 3864, 3192, 2520, 1860, 1236, 684, 252, 7644, 6468, 5292, 4130, 3010, 1974, 1078, 392, 13920, 12000, 10080, 8176, 6320, 4560, 2960, 1600, 576, 23760
OFFSET
0,2
COMMENTS
A193894 is obtained by reversing the rows of the triangle A193893.
FORMULA
Write w(n,k) for the triangle at A193893. The triangle at A193894 is then given by w(n,n-k).
EXAMPLE
First six rows:
1
4.....2
44....28....12
210...150...90....36
680...520...360...208..80
1750..1400..1050..710..400..105
MATHEMATICA
z = 9;
p[n_, x_] := Sum[(k + 1) (n + 1)*x^(n - k), {k, 0, n}]
q[n_, x_] := p[n, x];
t[n_, k_] := Coefficient[p[n, x], x^k]; t[n_, 0] := p[n, x] /. x -> 0;
w[n_, x_] := Sum[t[n, k]*q[n + 1 - k, x], {k, 0, n}]; w[-1, x_] := 1
g[n_] := CoefficientList[w[n, x], {x}]
TableForm[Table[Reverse[g[n]], {n, -1, z}]]
Flatten[Table[Reverse[g[n]], {n, -1, z}]] (* A193893 *)
TableForm[Table[g[n], {n, -1, z}]]
Flatten[Table[g[n], {n, -1, z}]] (* A193894 *)
CROSSREFS
Cf. A193893.
Sequence in context: A280780 A264755 A120968 * A107667 A362155 A163176
KEYWORD
nonn,tabl
AUTHOR
Clark Kimberling, Aug 08 2011
STATUS
approved