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A124574 Triangle read by rows: row n is the first row of the matrix M[n]^(n-1), where M[n] is the n X n tridiagonal matrix with main diagonal (3,4,4,...) and super- and subdiagonals (1,1,1,...). 25
1, 3, 1, 10, 7, 1, 37, 39, 11, 1, 150, 204, 84, 15, 1, 654, 1050, 555, 145, 19, 1, 3012, 5409, 3415, 1154, 222, 23, 1, 14445, 28063, 20223, 8253, 2065, 315, 27, 1, 71398, 146920, 117208, 55300, 16828, 3352, 424, 31, 1, 361114, 776286, 671052, 355236 (list; table; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

Column 1 yields A064613 (2nd binomial transform of the Catalan sequence A000108). Row sums yield A081671.

Triangle T(n,k), 0<=k<=n, defined by : T(0,0)=1, T(n,k)=0 if k<0 or if k>n, T(n,0)=3*T(n-1,0)+T(n-1,1), T(n,k)=T(n-1,k-1)+4*T(n-1,k)+T(n-1,k+1) . - Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Feb 27 2007

Triangle T(n,k), 0<=k<=n, read by rows given by : T(0,0)=1, T(n,k)=0 if k<0 or if k>n, T(n,0)=3*T(n-1,0)+T(n-1,1), T(n,k)=T(n-1,k-1)+4*T(n-1,k)+T(n-1,k+1) for k>=1 . - Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Mar 27 2007

This triangle belongs to the family of triangles defined by: T(0,0)=1, T(n,k)=0 if k<0 or if k>n, T(n,0)=x*T(n-1,0)+T(n-1,1), T(n,k)=T(n-1,k-1)+y*T(n-1,k)+T(n-1,k+1) for k>=1 . Other triangles arise by choosing different values for (x,y): (0,0) -> A053121; (0,1) -> A089942; (0,2) -> A126093; (0,3) -> A126970; (1,0)-> A061554; (1,1) -> A064189; (1,2) -> A039599; (1,3) -> A110877; ((1,4) -> A124576; (2,0) -> A126075; (2,1) -> A038622; (2,2) -> A039598; (2,3) -> A124733; (2,4) -> A124575; (3,0) -> A126953; (3,1) -> A126954; (3,2) -> A111418; (3,3) -> A091965; (3,4) -> A124574; (4,3) -> A126791; (4,4) -> A052179; (4,5) -> A126331; (5,5) -> A125906 . - Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Sep 25 2007

6^n = ((n+1)-th row terms) dot (first n+1 odd integers). Example: 6^4 = 1296 = (150, 204, 84, 15, 1) dot (1, 3, 5, 7, 9) = (150 + 612 + 420 + 105 + 9)= 1296. - Gary W. Adamson (qntmpkt(AT)yahoo.com), Jun 15 2011

FORMULA

Sum_{k, 0<=k<=n}(-1)^(n-k)*T(n,k)=(-2)^n . - Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Feb 27 2007

Sum_{k, 0<=k<=n}T(n,k)*(2*k+1)=6^n . - Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Mar 27 2007

EXAMPLE

Row 4 is (37,39,11,1) because M[4]= [3,1,0,0;1,4,1,0;0,1,4,1;0,0,1,4] and M[4]^3=[37,39,11,1; 39, 87, 51, 12; 11, 51, 88, 50; 1, 12, 50, 76].

Triangle starts:

1;

3, 1

10, 7, 1;

37, 39, 11, 1

150, 204, 84, 15, 1;

654, 1050, 555, 145, 19, 1;

Production matrix begins

3, 1

1, 4, 1

0, 1, 4, 1

0, 0, 1, 4, 1

0, 0, 0, 1, 4, 1

0, 0, 0, 0, 1, 4, 1

0, 0, 0, 0, 0, 1, 4, 1

0, 0, 0, 0, 0, 0, 1, 4, 1

0, 0, 0, 0, 0, 0, 0, 1, 4, 1

- From DELEHAM Philippe, Nov 07 2011

MAPLE

with(linalg): m:=proc(i, j) if i=1 and j=1 then 3 elif i=j then 4 elif abs(i-j)=1 then 1 else 0 fi end: for n from 3 to 11 do A[n]:=matrix(n, n, m): B[n]:=multiply(seq(A[n], i=1..n-1)) od: 1; 3, 1; for n from 3 to 11 do seq(B[n][1, j], j=1..n) od; # yields sequence in triangular form

CROSSREFS

Cf. A000108, A081671, A124575, A124576, A052179, A064613.

Sequence in context: A116384 A117207 A046658 * A052964 A084178 A195812

Adjacent sequences:  A124571 A124572 A124573 * A124575 A124576 A124577

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson & Roger L. Bagula (qntmpkt(AT)yahoo.com), Nov 04 2006

EXTENSIONS

Edited by N. J. A. Sloane (njas(AT)research.att.com), Dec 04 2006

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Last modified February 13 20:26 EST 2012. Contains 205553 sequences.