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A114284 Riordan array ((1-3x)/(1-x),x). 2
1, -2, 1, -2, -2, 1, -2, -2, -2, 1, -2, -2, -2, -2, 1, -2, -2, -2, -2, -2, 1, -2, -2, -2, -2, -2, -2, 1, -2, -2, -2, -2, -2, -2, -2, 1, -2, -2, -2, -2, -2, -2, -2, -2, 1, -2, -2, -2, -2, -2, -2, -2, -2, -2, 1, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Inverse of A114283. Row sums are 1-2n. Diagonal sums are A114285. Sequence array of 3*0^n-2.

LINKS

Table of n, a(n) for n=0..65.

FORMULA

T(n, k)=if(k<=n, 3*0^(n-k)-2, 0)

a(n) =-3 floor(1/2 sqrt(8 x+1)-1/2)+3 floor(1/2 sqrt(8 x+9)-1/2)-2 (* From Jackson Xier, Oct 07 2011 *)

EXAMPLE

Triangle begins

1;

-2,1;

-2,-2,1;

-2,-2,-2,1;

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

MATHEMATICA

Table[-2 - 3 Floor[1/2 (-1 + Sqrt[1 + 8 x])] +

  3 Floor[1/2 (-1 + Sqrt[9 + 8 x])], {x, 0, 250}]  (* From Jackson Xier, Oct 07 2011 *)

CROSSREFS

Sequence in context: A265404 A274353 A183028 * A238303 A023575 A215113

Adjacent sequences:  A114281 A114282 A114283 * A114285 A114286 A114287

KEYWORD

easy,sign,tabl

AUTHOR

Paul Barry, Nov 20 2005

STATUS

approved

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Last modified February 19 16:02 EST 2019. Contains 320311 sequences. (Running on oeis4.)