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A219325
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Positive integers n that are equal to the determinant of the circulant matrix formed by the binary digits of n.
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6
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OFFSET
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1,2
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LINKS
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Table of n, a(n) for n=1..8.
Giovanni Resta, Illustration of a(8)
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EXAMPLE
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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.
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MATHEMATICA
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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 *)
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CROSSREFS
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Cf. A219324 (decimal version) provides references and more details.
Sequence in context: A230164 A001381 A219357 * A255780 A023942 A322858
Adjacent sequences: A219322 A219323 A219324 * A219326 A219327 A219328
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KEYWORD
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base,nonn,nice,more
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AUTHOR
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Max Alekseyev, Nov 17 2012
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EXTENSIONS
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a(7) from Hans Havermann and Emmanuel Vantieghem, Nov 19 2012
a(8) from Giovanni Resta, Dec 14 2012
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STATUS
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approved
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