%I A054521
%S A054521 1,1,0,1,1,0,1,0,1,0,1,1,1,1,0,1,0,0,0,1,0,1,1,1,1,1,1,0,1,0,1,
%T A054521 0,1,0,1,0,1,1,0,1,1,0,1,1,0,1,0,1,0,0,0,1,0,1,0,1,1,1,1,1,1,1,
%U A054521 1,1,1,0,1,0,0,0,1,0,1,0,0,0,1,0,1,1,1,1,1,1,1,1,1,1,1,1,0,1,0
%N A054521 Triangle T(n,k): T(n,k)=1 if GCD(n,k) = 1, T(n,k)=0 otherwise (n >= 1, 
               1<=k<=n).
%C A054521 Row sums = phi(n), A000010: (1, 1, 2, 2, 4, 2, 6,...). - Gary W. Adamson 
               (qntmpkt(AT)yahoo.com), May 20 2007
%Y A054521 Cf. A051731, A054522, ...
%Y A054521 Cf. A054521.
%Y A054521 Sequence in context: A143242 A136442 A128431 this_sequence A014240 A014471 
               A071028
%Y A054521 Adjacent sequences: A054518 A054519 A054520 this_sequence A054522 A054523 
               A054524
%K A054521 nonn,tabl
%O A054521 1,1
%A A054521 N. J. A. Sloane (njas(AT)research.att.com), Apr 09 2000