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A115513 Inverse of matrix (1,x)+(x,x^3). 1
1, -1, 1, 0, 0, 1, 0, 0, 0, 1, 1, -1, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, -1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, -1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 1, 0, 0, -1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Row sums are A014578(n+5) or sum{k=0..ceiling(log(n+4)/log(3)),(-1)^k*(floor((n+4)/3^k)-floor((n+3)/3^k)}. Inverse of number triangle A115512.

LINKS

Table of n, a(n) for n=0..118.

EXAMPLE

Triangle begins

1,

-1, 1,

0, 0, 1,

0, 0, 0, 1,

1, -1, 0, 0, 1,

0, 0, 0, 0, 0, 1,

0, 0, 0, 0, 0, 0, 1,

0, 0, -1, 0, 0, 0, 0, 1,

0, 0, 0, 0, 0, 0, 0, 0, 1,

0, 0, 0, 0, 0, 0, 0, 0, 0, 1,

0, 0, 0, -1, 0, 0, 0, 0, 0, 0, 1,

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1,

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1,

-1, 1, 0, 0, -1, 0, 0, 0, 0, 0, 0, 0, 0, 1,

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1

CROSSREFS

Sequence in context: A128189 A303340 A115512 * A133080 A316917 A133985

Adjacent sequences:  A115510 A115511 A115512 * A115514 A115515 A115516

KEYWORD

sign,tabl

AUTHOR

Paul Barry, Jan 23 2006

STATUS

approved

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Last modified June 13 00:57 EDT 2021. Contains 344980 sequences. (Running on oeis4.)