The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation. Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A306595 Determinant of the circulant matrix whose first column corresponds to the binary digits of n. 2
 0, 1, 1, 0, 1, 2, 2, 0, 1, 0, 0, 3, 0, -3, 3, 0, 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 0, 1, 0, 4, 0, 0, -9, 9, 0, 4, 9, 0, 8, 9, 0, 8, 5, 0, 0, 9, 0, -9, -8, 0, -5, 0, 0, 8, 5, 0, -5, 5, 0, 1, 2, 2, 3, 2, 24, 24, 4, 2, 3, 3, 32, 3, 4, 32, 5, 2, 24, 3 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,6 COMMENTS This sequence is the binary variant of A177894. From Robert Israel, Mar 05 2019: (Start) a(n) is divisible by A000120(n). If A070939(n) is even then n is divisible by A000120(n)*A065359(n). (End) LINKS Robert Israel, Table of n, a(n) for n = 0..10000 Wikipedia, Circulant matrix FORMULA a(A121016(n)) = 0 for any n > 0. a(2^k) = 1 for any k >= 0. a(A219325(n)) = A219325(n) for any n > 0. EXAMPLE For n = 13: - the binary representation of 13 is "1101", - the corresponding circulant matrix is:     [1 1 0 1]     [1 1 1 0]     [0 1 1 1]     [1 0 1 1] - its determinant is -3, - hence a(13) = -3. MAPLE a:= n-> `if`(n=1, 1, (l-> LinearAlgebra[Determinant](Matrix(nops(l),        shape=Circulant[l[-i]\$i=1..nops(l)])))(convert(n, base, 2))): seq(a(n), n=0..100);  # Alois P. Heinz, Mar 05 2019 PROG (PARI) a(n) = my (d=if (n, binary(n), )); my (m=matrix(#d, #d, i, j, d[1+(i-j)%#d])); return (matdet(m)) CROSSREFS Cf. A000120, A065359,  A070939, A121016, A177894, A219325, A306714. Sequence in context: A049502 A242284 A333624 * A332996 A292592 A292274 Adjacent sequences:  A306592 A306593 A306594 * A306596 A306597 A306598 KEYWORD sign,base,look AUTHOR Rémy Sigrist, Feb 27 2019 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified June 18 04:41 EDT 2021. Contains 345098 sequences. (Running on oeis4.)