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%I #11 Mar 23 2024 17:31:28
%S 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,
%T 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,
%U 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
%N Square array read by antidiagonals up. Redheffer type matrix. T(1,1)=1 and T(n,1) = A049240.
%C 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.
%e The array begins:
%e 1,1,1,1,1,1,1,1,1,1
%e 1,1,0,0,0,0,0,0,0,0
%e 1,0,1,0,0,0,0,0,0,0
%e 0,1,0,1,0,0,0,0,0,0
%e 1,0,0,0,1,0,0,0,0,0
%e 1,1,1,0,0,1,0,0,0,0
%e 1,0,0,0,0,0,1,0,0,0
%e 1,1,0,1,0,0,0,1,0,0
%e 0,0,1,0,0,0,0,0,1,0
%e 1,1,0,0,1,0,0,0,0,1
%t 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 *)
%Y Cf. A143104, A002819, A174854, A174852.
%K nonn,tabl
%O 1,1
%A _Mats Granvik_, Mar 31 2010