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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)
OFFSET

1,2

LINKS

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

Giovanni Resta, Illustration of a(8)

EXAMPLE

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.

MATHEMATICA

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 *)

CROSSREFS

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

KEYWORD

base,nonn,nice,more

AUTHOR

Max Alekseyev, Nov 17 2012

EXTENSIONS

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

a(8) from Giovanni Resta, Dec 14 2012

STATUS

approved

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Last modified August 3 01:36 EDT 2021. Contains 346429 sequences. (Running on oeis4.)