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A104967 Matrix inverse of triangle A104219, read by rows, where A104219(n,k) equals the number of Schroeder paths of length 2n having k peaks at height 1. +0
5
1, -1, 1, -1, -2, 1, -1, -1, -3, 1, -1, 0, 0, -4, 1, -1, 1, 2, 2, -5, 1, -1, 2, 3, 4, 5, -6, 1, -1, 3, 3, 3, 5, 9, -7, 1, -1, 4, 2, 0, 0, 4, 14, -8, 1, -1, 5, 0, -4, -6, -6, 0, 20, -9, 1, -1, 6, -3, -8, -10, -12, -14, -8, 27, -10, 1, -1, 7, -7, -11, -10, -10, -14, -22, -21, 35, -11, 1, -1, 8, -12, -12, -5, 0, 0, -8, -27, -40, 44, -12, 1 (list; table; graph; listen)
OFFSET

0,5

COMMENT

Row sums equal A090132 with odd-indexed terms negated. Absolute row sums form A104968. Row sums of squared terms gives A104969.

FORMULA

G.f.: A(x, y) = (1-2*x)/(1-x - x*y*(1-2*x)).

EXAMPLE

Triangle begins:

1;

-1,1;

-1,-2,1;

-1,-1,-3,1;

-1,0,0,-4,1;

-1,1,2,2,-5,1;

-1,2,3,4,5,-6,1;

-1,3,3,3,5,9,-7,1;

-1,4,2,0,0,4,14,-8,1;

-1,5,0,-4,-6,-6,0,20,-9,1; ...

PROGRAM

(PARI) {T(n, k)=local(X=x+x*O(x^n), Y=y+y*O(y^k)); polcoeff(polcoeff((1-2*X)/(1-X-X*Y*(1-2*X)), n, x), k, y)}

CROSSREFS

Cf. A090132, A104969, A104969.

Sequence in context: A073266 A125692 A128258 this_sequence A098495 A095025 A069897

Adjacent sequences: A104964 A104965 A104966 this_sequence A104968 A104969 A104970

KEYWORD

sign,tabl

AUTHOR

Paul D. Hanna (pauldhanna(AT)juno.com), Mar 30 2005

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Last modified July 26 23:19 EDT 2008. Contains 142293 sequences.


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