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A086810 Triangle obtained by adding a leading diagonal 1,0,0,0,... to A033282. 17
1, 0, 1, 0, 1, 2, 0, 1, 5, 5, 0, 1, 9, 21, 14, 0, 1, 14, 56, 84, 42, 0, 1, 20, 120, 300, 330, 132, 0, 1, 27, 225, 825, 1485, 1287, 429, 0, 1, 35, 385, 1925, 5005, 7007, 5005, 1430, 0, 1, 44, 616, 4004, 14014, 28028, 32032, 19448, 4862, 0, 1, 54, 936, 7644, 34498, 91728 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,6

COMMENTS

Mirror image of triangle A133336 . [From Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Dec 10 2008]

Contribution from Tom Copeland, Oct 09 2011: (Start)

With polynomials

P(0,t) = 0

P(1,t) = 1

P(2,t) = t

P(3,t) = t + 2 t^2

P(4,t) = t + 5 t^2 +  5 t^3)

P(5,t) = t + 9 t^2 +  21 t^3 + 14 t^4

The o.g.f. A(x,t)= {1+x-sqrt[(1-x)^2-4xt]}/[2(1+t)], (see Drake et al.).

B(x,t)= x-t x^2/(1-x)= x-t(x^2+x^3+x^4+...) is the comp. inverse in x.

Let h(x,t)= 1/(dB/dx)= (1-x)^2/[1+(1+t)*x*(x-2)]=1/[1-t[2x+3x^2+4x^3+...]], an o.g.f. in x for row polynomials in t of A181289. Then P(n,t), is given by (1/n!)(h(x,t)*d/dx)^n x, evaluated at x=0, A=exp(x*h(y,t)*d/dy) y, eval. at y=0, and dA/dx = h(A(x,t),t). These results are a special case of A133437 with u(x,t)= B(x,t), i.e., u_1=1 and (u_n)=-t for n>1. See A001003 for t = 1. (End)

LINKS

Brian Drake, Ira M. Gessel, and Guoce Xin, Three Proofs and a Generalization of the Goulden-Litsyn-Shevelev Conjecture on a Sequence Arising in Algebraic Geometry, J. of Integer Sequences, Vol. 10 (2007), Article 07.3.7

FORMULA

Triangle T(n, k) read by rows; given by [0, 1, 0, 1, 0, 1, ...] DELTA [1, 1, 1, 1, 1, 1, 1, 1, 1, ...] where DELTA is Deleham's operator defined in A084938.

For k>0, T(n, k) = binomial(n+k-1, n)*binomial(n+2k, k)/(n+k+1); T(0, 0) = 1 and T(n, 0) = 0 if n>0.

Sum_{k>=0} T(n, k)*2^k = A107841(n) . - Philippe DELEHAM (kolotoko(AT)wanadoo.fr), May 26 2005

Sum_{ k>=0} T(n-k, k) = A005043(n) . - Philippe DELEHAM, May 30 2005

T(n, k) = A108263(n+k, k) . - Philippe DELEHAM, May 30 2005

Sum_{k, 0<=k<=n}T(n,k)*x^k = A000007(n), A001003(n), A107841(n), A131763(n), A131765(n), A131846(n), A131926(n), A131869(n), A131927(n) for x = 0, 1, 2, 3, 4, 5, 6, 7, 8 respectively . - Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Nov 05 2007

Sum_{k, 0<=k<=n}T(n,k)*5^k*(-2)^(n-k) = A152601(n). [From Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Dec 10 2008]

Sum_{k, 0<=k<=n}T(n,k)*(-1)^k*3^(n-k) = A154825(n). [From Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Jan 17 2009]

EXAMPLE

1; 0, 1; 0, 1, 2; 0, 1, 5, 5; 0, 1, 9, 21, 14; ...

CROSSREFS

Diagonals : A000007, A000012, A000096, A033275, A033276, A033277, A033278, A033279, A000108, A002054, A002055, A002056, A007160, A033280, A033281

The diagonals (except for A000007) are also the diagonals of A033282.

Row sums : A001003 (Schroeder numbers)

Cf. A033282, A084938.

Sequence in context: A085650 A201910 A109450 * A085838 A094456 A010028

Adjacent sequences:  A086807 A086808 A086809 * A086811 A086812 A086813

KEYWORD

easy,nonn,tabl

AUTHOR

DELEHAM Philippe (kolotoko(AT)wanadoo.fr), Aug 05 2003

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Last modified February 17 02:48 EST 2012. Contains 205978 sequences.