A174856 Square array read by antidiagonals up. Redheffer type matrix. T(1,1)=1 and T(n,1) = A049240.

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

Offset: 1

Author

Mats Granvik, Mar 31 2010

Keywords

• nonn
• tabl

Comments

The first column is equal to 0 when n is a square greater than 1. The rest of the array is equal to A143104. The determinant of this array is A002819.

Examples

			The array begins:
  1,1,1,1,1,1,1,1,1,1
  1,1,0,0,0,0,0,0,0,0
  1,0,1,0,0,0,0,0,0,0
  0,1,0,1,0,0,0,0,0,0
  1,0,0,0,1,0,0,0,0,0
  1,1,1,0,0,1,0,0,0,0
  1,0,0,0,0,0,1,0,0,0
  1,1,0,1,0,0,0,1,0,0
  0,0,1,0,0,0,0,0,1,0
  1,1,0,0,1,0,0,0,0,1
		

Crossrefs

Cf. A143104, A002819, A174854, A174852.

Programs

Mathematica

t[1, 1] = 1; t[n_, 1] := Boole[!IntegerQ[Sqrt[n]]]; t[n_, k_] := Boole[n == 1 || Mod[n, k] == 0]; Table[t[n - k + 1, k], {n, 1, 14}, {k, 1, n}] // Flatten (* Jean-François Alcover, Dec 05 2013 *)