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A193723 Mirror of the fusion triangle A193722. 5
1, 2, 1, 6, 5, 1, 18, 21, 8, 1, 54, 81, 45, 11, 1, 162, 297, 216, 78, 14, 1, 486, 1053, 945, 450, 120, 17, 1, 1458, 3645, 3888, 2295, 810, 171, 20, 1, 4374, 12393, 15309, 10773, 4725, 1323, 231, 23, 1, 13122, 41553, 58320, 47628, 24948, 8694, 2016, 300, 26, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

A193723 is obtained by reversing the rows of the triangle A193722.

Triangle T(n,k), read by rows, given by [2,1,0,0,0,0,0,0,0,...] DELTA [1,0,0,0,0,0,0,0,...] where DELTA is the operator defined in A084938. [from Philippe Deléham, Oct 04 2011]

Contribution from Philippe Deléham, Nov 14 2011 : (Start)

Riordan array ((1-x)/(1-3x),x/(1-3x)).

Product A200139*A007318 as infinite lower triangular arrays. (End)

LINKS

Table of n, a(n) for n=0..54.

FORMULA

Write w(n,k) for the triangle at A193722.  The triangle at A193723 is then given by w(n,n-k).

T(n,k)=T(n-1,k-1)+3*T(n-1,k)with T(0,0)=T(1,1)=1 and T(1,0)=2 - From Philippe Deléham, Oct 05 2011.

Contribution from Philippe Deléham, Nov 14 2011 :(Start)

Sum_{k, 0<=k<=n} T(n,k)*x^k = A000007(n), A011782(n), A025192(n), A002001(n), A005054(n), A052934(n), A055272(n), A055274(n), A055275(n), A052268(n), A055276(n), A196731(n) for x=-2,-1,0,1,2,3,4,5,6,7,8,9 respectively.

T(n,k)= Sum_{j>=0} T(n-1-j,k-1)*3^j.

G.f.: (1-x)/(1-(3+y)*x).

EXAMPLE

First six rows:

1

2....1

6....5....1

18...21...8....1

54...81...45...11..1

162..297..216..78..14..1

MATHEMATICA

z = 9; a = 1; b = 1; c = 1; d = 2;

p[n_, x_] := (a*x + b)^n ; q[n_, x_] := (c*x + d)^n

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}]] (* A193722 *)

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

Flatten[Table[g[n], {n, -1, z}]] (* A193723 *)

CROSSREFS

Cf. A084938, A193722, A052924(antidiagonal sums), Diagonals : A000012, A016789, A081266 , Columns : A025192, A081038.

Sequence in context: A294439 A008970 A055896 * A260914 A159965 A116395

Adjacent sequences:  A193720 A193721 A193722 * A193724 A193725 A193726

KEYWORD

nonn,tabl

AUTHOR

Clark Kimberling, Aug 04 2011

STATUS

approved

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Last modified February 18 20:32 EST 2018. Contains 299330 sequences. (Running on oeis4.)