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A161780 Square array read by antidiagonals up. Redheffer type matrix. A007427 interleaved with k-1 zeros in the columns. 0
1, -2, 1, -2, 1, 1, 1, 0, 0, 1, -2, -2, 1, 0, 1, 4, 0, 0, 0, 0, 1, -2, -2, 0, 1, 0, 0, 1, 0, 0, -2, 0, 0, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 0, 1, 4, 0, 0, 0, 0, 0, 0, 0, 0, 1, -2, -2, -2, -2, 0, 1, 0, 0, 0, 0, 1, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -2, 4, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 4, 0, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The determinant of this matrix is A006218.

LINKS

Table of n, a(n) for n=1..94.

EXAMPLE

Table begins:

..1..1..1..1..1..1..1..1

.-2..1..0..0..0..0..0..0

.-2..0..1..0..0..0..0..0

..1.-2..0..1..0..0..0..0

.-2..0..0..0..1..0..0..0

..4.-2.-2..0..0..1..0..0

.-2..0..0..0..0..0..1..0

..0..1..0.-2..0..0..0..1

PROG

(Excel): =if(row()=1; 1; if(mod(row(); column())=0; 1*lookup(row()/column(); A000027; A007427); 0))

CROSSREFS

Cf. A007427, A006218, A002321.

Sequence in context: A078508 A029416 A252374 * A136571 A178562 A232624

Adjacent sequences:  A161777 A161778 A161779 * A161781 A161782 A161783

KEYWORD

sign,tabl

AUTHOR

Mats Granvik, Jun 19 2009

STATUS

approved

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Last modified March 28 21:25 EDT 2017. Contains 284246 sequences.