Sums of antidiagonals of A107267.

Terms

a(0) =1a(1) =1a(2) =2a(3) =5a(4) =14a(5) =46a(6) =173a(7) =733a(8) =3436a(9) =17572a(10) =96997a(11) =573268a(12) =3604687a(13) =23990345a(14) =168254444a(15) =1238889493a(16) =9546211068a(17) =76761000444a(18) =642524333589