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%I #16 Jan 28 2021 20:54:09
%S 1,1,3,126,11340,5940840,12076523928,95052257647200,
%T 3153668941285723200,406198470650573931200640,
%U 215366179177149634500004545792,447870507819487666185959047316144640,3770394197251690930118967532374966498493440,126205342254129164806148123600990735262978861434880,16960349752279776751561660450391351891796348875427924676608
%N a(n) = number of squares in GL(n,2), the ring of invertible n X n matrices over GF(2).
%H Victor S. Miller, <a href="http://arxiv.org/abs/1606.09299">Counting Matrices that are Squares</a>, arXiv:1606.09299 [math.GR], 2016.
%H <a href="/index/Mat#binmat">Index entries for matrices, binary, which are squares</a>
%Y Cf. A266462, A274313, A225371.
%K nonn
%O 0,3
%A _N. J. A. Sloane_, Jun 25 2016