OFFSET
0,4
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..8191
Wikipedia, Circulant matrix
Wikipedia, Permanent (mathematics)
FORMULA
EXAMPLE
The circulant matrix for n = 23 = 10111_2 is
[1 0 1 1 1]
[1 1 0 1 1]
[1 1 1 0 1]
[1 1 1 1 0]
[0 1 1 1 1] and has permanent 44, thus a(23) = 44.
a(10) = 4 != a(12) = 2 although 10 = 1010_2 and 12 = 1100_2 have the same number of 0's and 1's.
MAPLE
a:= n-> (l-> LinearAlgebra[Permanent](Matrix(nops(l),
shape=Circulant[l])))(convert(n, base, 2)):
seq(a(n), n=0..100);
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Alois P. Heinz, Mar 05 2019
STATUS
approved