login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

Mirror of the triangle A193792.
2

%I #4 Mar 30 2012 18:57:38

%S 1,1,1,4,1,3,16,1,6,9,64,1,9,27,27,256,1,12,54,108,81,1024,1,15,90,

%T 270,405,243,4096,1,18,135,540,1215,1458,729,16384,1,21,189,945,2835,

%U 5103,5103,2187,65536,1,24,252,1512,5670,13608,20412,17496,6561

%N Mirror of the triangle A193792.

%C A193793 is obtained by reversing the rows of the triangle A193792.

%F Write w(n,k) for the triangle at A193792. The triangle at A193793 is then given by w(n,n-k).

%e First six rows:

%e 1

%e 1....1

%e 4....1....3

%e 16....1....6....9

%e 64..1....9....27...27

%e 256...1...12....54...108....81

%t z = 8; a = 1; b = 3;

%t p[n_, x_] := (a*x + b)^n

%t q[n_, x_] := 1 + x^n ; q[n_, 0] := q[n, x] /. x -> 0;

%t t[n_, k_] := Coefficient[p[n, x], x^k]; t[n_, 0] := p[n, x] /. x -> 0;

%t w[n_, x_] := Sum[t[n, k]*q[n + 1 - k, x], {k, 0, n}]; w[-1, x_] := 1

%t g[n_] := CoefficientList[w[n, x], {x}]

%t TableForm[Table[Reverse[g[n]], {n, -1, z}]]

%t Flatten[Table[Reverse[g[n]], {n, -1, z}]] (* A193792 *)

%t TableForm[Table[g[n], {n, -1, z}]]

%t Flatten[Table[g[n], {n, -1, z}]] (* A193793 *)

%Y Cf. A193792.

%K nonn,tabl

%O 0,4

%A _Clark Kimberling_, Aug 05 2011