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A193861
Mirror of the triangle A193860.
3
1, 5, 1, 19, 7, 1, 65, 33, 9, 1, 211, 131, 51, 11, 1, 665, 473, 233, 73, 13, 1, 2059, 1611, 939, 379, 99, 15, 1, 6305, 5281, 3489, 1697, 577, 129, 17, 1, 19171, 16867, 12259, 6883, 2851, 835, 163, 19, 1, 58025, 52905, 41385, 26025, 12585, 4521, 1161
OFFSET
0,2
COMMENTS
A193861 is obtained by reversing the rows of the triangle A193860.
FORMULA
Write w(n,k) for the triangle at A193860. The triangle at A193861 is then given by w(n,n-k).
EXAMPLE
First six rows:
1
5.....1
19....7.....1
65....33....9.....1
211...131...51....11...1
665...473...233...73...13...1
MATHEMATICA
z = 10;
p[n_, x_] := (2 x + 1)^n;
q[0, x_] := 1; q[n_, x_] := x*q[n - 1, x] + 1;
p1[n_, k_] := Coefficient[p[n, x], x^k];
p1[n_, 0] := p[n, x] /. x -> 0;
d[n_, x_] := Sum[p1[n, k]*q[n - 1 - k, x], {k, 0, n - 1}]
h[n_] := CoefficientList[d[n, x], {x}]
TableForm[Table[Reverse[h[n]], {n, 0, z}]]
Flatten[Table[Reverse[h[n]], {n, -1, z}]] (* A193860 *)
TableForm[Table[h[n], {n, 0, z}]]
Flatten[Table[h[n], {n, -1, z}]] (* A193861 *)
CROSSREFS
Cf. A193860.
Sequence in context: A297174 A226605 A055584 * A349544 A193857 A146055
KEYWORD
nonn,tabl
AUTHOR
Clark Kimberling, Aug 07 2011
STATUS
approved