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%I #8 Mar 16 2022 02:52:33
%S 1,3,7,16,46,138,601,2619,16162,93531,654700,4442304
%N Maximal sum of inverse squares of the singular values of Toeplitz anti-Hadamard matrices of order n.
%H R. L. Graham and N. J. A. Sloane, <a href="http://dx.doi.org/10.1016/0024-3795(84)90090-9">Anti-Hadamard matrices</a>, Linear Alg. Applic., 62 (1984), 113-137, Table 1.
%Y Cf. A005312, A005313, A351240, A351241.
%K nonn,hard,more
%O 1,2
%A _Stefano Spezia_, Feb 20 2022
%E a(12) confirmed and inserted by _Stefano Spezia_, Mar 16 2022