Number of traceless symmetric binary matrices with 2n 1's and all row sums >= 2.

A370059

Number of traceless symmetric binary matrices with 2n 1's and all row sums >= 2.

Terms

    a(0) =1a(1) =0a(2) =0a(3) =1a(4) =3a(5) =18a(6) =156a(7) =1555a(8) =17907a(9) =234031a(10) =3414375a(11) =54984258a(12) =968680368a(13) =18532158756a(14) =382616109012

External references