login
Square array read by antidiagonals up. Redheffer type matrix. A007427 interleaved with k-1 zeros in the columns.
0

%I #7 Feb 18 2024 01:27:16

%S 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,

%T 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,

%U 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

%N Square array read by antidiagonals up. Redheffer type matrix. A007427 interleaved with k-1 zeros in the columns.

%C The determinant of this matrix is A006218.

%e Table begins:

%e ..1..1..1..1..1..1..1..1

%e .-2..1..0..0..0..0..0..0

%e .-2..0..1..0..0..0..0..0

%e ..1.-2..0..1..0..0..0..0

%e .-2..0..0..0..1..0..0..0

%e ..4.-2.-2..0..0..1..0..0

%e .-2..0..0..0..0..0..1..0

%e ..0..1..0.-2..0..0..0..1

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

%Y Cf. A007427, A006218, A002321.

%K sign,tabl

%O 1,2

%A _Mats Granvik_, Jun 19 2009