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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
OFFSET
1,2
COMMENTS
The determinant of this matrix is A006218.
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
KEYWORD
sign,tabl
AUTHOR
Mats Granvik, Jun 19 2009
STATUS
approved