OFFSET
1,4
COMMENTS
Det(Q_n) = 1 if Q_n denotes the n X n matrix defined by: m(i,j)=1 if floor(i/j) is odd, 0 otherwise, since this matrix is triangular with 1's on the main diagonal.
PROG
(PARI) for(n=1, 70, print1(matdet(matrix(n, n, i, j, if((-1)^(sigma(i+j))+1, 1, 0))), ", "))
CROSSREFS
KEYWORD
easy,sign
AUTHOR
Benoit Cloitre, May 30 2002
STATUS
approved