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A167431 Riordan array (1-4x+4x^2, x(1-2x)). 4

%I

%S 1,-4,1,4,-6,1,0,12,-8,1,0,-8,24,-10,1,0,0,-32,40,-12,1,0,0,16,-80,60,

%T -14,1,0,0,0,80,-160,84,-16,1,0,0,0,-32,240,-280,112,-18,1,0,0,0,0,

%U -192,560,-448,144,-20,1,0,0,0,0,64,-672,1120,-672,180,-22,1

%N Riordan array (1-4x+4x^2, x(1-2x)).

%C Row sums are A167433. Diagonal sums are A167434. Central coefficients are (-1)^n*A001788(n+1).

%C Inverse is A167432.

%F T(n,k)=T(n-1,k-1)-2*T(n-2,k-1), T(0,0)=1, T(1,0)=-4, T(2,0)=4, T(n,k)=0 if k<0 or if k>n. - _Philippe Deléham_, Nov 13 2013

%e Triangle begins

%e 1,

%e -4, 1,

%e 4, -6, 1,

%e 0, 12, -8, 1,

%e 0, -8, 24, -10, 1,

%e 0, 0, -32, 40, -12, 1,

%e 0, 0, 16, -80, 60, -14, 1,

%e 0, 0, 0, 80, -160, 84, -16, 1,

%e 0, 0, 0, -32, 240, -280, 112, -18, 1,

%e 0, 0, 0, 0, -192, 560, -448, 144, -20, 1,

%e 0, 0, 0, 0, 64, -672, 1120, -672, 180, -22, 1

%K easy,sign,tabl

%O 0,2

%A _Paul Barry_, Nov 03 2009

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Last modified May 28 18:24 EDT 2022. Contains 354122 sequences. (Running on oeis4.)