Left-hand edge of triangle in A097474.

A097716

Left-hand edge of triangle in A097474.

Terms

    a(0) =1a(1) =-1a(2) =2a(3) =-17a(4) =124a(5) =-2764a(6) =43688a(7) =-1859138a(8) =51236656a(9) =-3550889296a(10) =151107728672

External references