-720000

Appears in sequences

• A triangular sequence based on a two sequence lower triangular matrix. a(n)=(-1)^n*(n-1)!; b[n]=(n-1)!; M(i,j)={{a(i),b(j)},{b(j),a(i+1)}}; a0(i,j)=Det[M(i,j)]; This method gives an tridiagonal matrix effect to a lower triangular matrix base.at n=15A135281