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A140216 Numerators of the inverse triangle defined in A133135. 1
1, -1, 1, 1, -3, 1, -1, 3, -2, 1, 1, -5, 2, -5, 1, -1, 5, -1, 5, -3, 1, 1, -7, 1, 0, 3, -7, 1, -1, 7, -4, 0, 2, 7, -4, 1, 1, 3, 4, -21, -2, 21, 4, -9, 1, -1, -3, 13, 21, -26, -21, 10, 9, -5, 1, 1, -121, -13, 66, 26, -231, -10, 33, 5, -11, 1, -1, 121, -142, -66, 229, 231, -116, -33, 25, 11, -6 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,5

COMMENTS

Row sums 1, 0, -1, 1, -6, 6, -8, 8, 2, -2,.. build in pairs.

LINKS

Table of n, a(n) for n=0..76.

EXAMPLE

The triangle starts

1;

-1, 1;

1,-3, 1;

-1, 3,-2, 1;

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

-1, 5,-1, 5, -3, 1;

1,-7, 1, 0, 3, -7, 1;

-1, 7,-4, 0, 2, 7,-4, 1;

1, 3, 4,-21, -2, 21, 4,-9, 1;

-1,-3,13, 21,-26,-21,10, 9,-5,1;

Pairs of numbers appear along adjacent diagonals. The first subdiagonal contains the sequence -A026741(n+2).

CROSSREFS

Cf. A133135, A140218.

Sequence in context: A233508 A106749 A225224 * A176514 A238559 A077196

Adjacent sequences:  A140213 A140214 A140215 * A140217 A140218 A140219

KEYWORD

sign,frac,tabl

AUTHOR

Paul Curtz, Jun 22 2008

EXTENSIONS

Edited by R. J. Mathar, Aug 06 2008

STATUS

approved

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Last modified May 13 01:10 EDT 2021. Contains 343829 sequences. (Running on oeis4.)