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A219325 Positive integers n that are equal to the determinant of the circulant matrix formed by the binary digits of n. 6
1, 17298, 25947, 100990, 106090, 2718340, 36680364, 34505916416 (list; graph; refs; listen; history; text; internal format)



Table of n, a(n) for n=1..8.

Giovanni Resta, Illustration of a(8)


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.


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 *)


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




Max Alekseyev, Nov 17 2012


a(7) from Hans Havermann and Emmanuel Vantieghem, Nov 19 2012

a(8) from Giovanni Resta, Dec 14 2012



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Last modified December 7 00:09 EST 2019. Contains 329812 sequences. (Running on oeis4.)