Number of n X n symmetric positive semi-definite matrices with 2's on the main diagonal and -1's and 0's elsewhere.

A084553

Number of n X n symmetric positive semi-definite matrices with 2's on the main diagonal and -1's and 0's elsewhere.

Terms

    a(0) =1a(1) =2a(2) =8a(3) =45a(4) =338a(5) =3178a(6) =34346a(7) =396659a(8) =4694705

External references