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%I #32 Sep 12 2023 15:49:13
%S 1,17298,25947,100990,106090,2718340,36680364,34505916416
%N Positive integers n that are equal to the determinant of the circulant matrix formed by the binary digits of n.
%H Giovanni Resta, <a href="/A219325/a219325.txt">Illustration of a(8)</a>
%e Binary digits of 17298 are [1, 0, 0, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0]. The 15 X 15 circulant matrix formed by their circular right rotations has determinant equal to 17298.
%t dcmQ[n_]:=Module[{idn2=IntegerDigits[n,2]},Det[Table[RotateRight[idn2,k],{k,Length[ idn2]}]] == n]; Select[Range[3*10^6],dcmQ] (* This program generates the first 6 terms of the sequence. To generate a(7) and a(8), increase the Range constant to 3451*10^7, but the program will take a long time to run. *) (* _Harvey P. Dale_, Jul 30 2019 *)
%Y Cf. A219324 (decimal version) provides references and more details.
%K base,nonn,nice,more
%O 1,2
%A _Max Alekseyev_, Nov 17 2012
%E a(7) from _Hans Havermann_ and _Emmanuel Vantieghem_, Nov 19 2012
%E a(8) from _Giovanni Resta_, Dec 14 2012
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