A071859 Determinant of M_n where M_n is the n X n matrix m_(i,j) = A030300(i+j).

0, 0, -1, 1, 1, -1, 0, 0, 1, 1, -1, -1, 0, 0, -1, 1, 1, 1, -2, 2, 3, -3, -1, 1, -2, -2, 1, 1, 1, -1, 0, 0, 1, 1, -1, 1, 2, -2, -1, -1, 3, 3, -2, -2, -1, 1, -1, -1, 0, 0, 1, -1, -1, 1, 0, 0, 1, 1, -1, -1, 0, 0, -1, 1, 1, 1, -2, 2, 3, -3, -1, -1, 4, 4, -3, -3

Offset: 1

Author

Benoit Cloitre, Jun 09 2002

Keywords

• easy
• sign

Comments

a(n)=0 for n=1,2,7,8,13,14,31,32,49,50,55,56,61,62...hence if a(n)=0, n odd it seems that a(n+1)=0. It seems also that if a(n)=0 (n odd ) then n == 1 mod 6 (converse doesn't hold).

Crossrefs

Cf. A030300.

Programs

PARI

for(n=1,70,print1(matdet(matrix(n,n,i,j,length(binary(j+i))%2)),","))

Extensions

Name corrected by Nathaniel Johnston, Sep 26 2011