Antidiagonal sums of square table A086626.

Terms

a(0) =1a(1) =2a(2) =3a(3) =8a(4) =23a(5) =70a(6) =230a(7) =782a(8) =2729a(9) =9740a(10) =35345a(11) =130018a(12) =483782a(13) =1817450a(14) =6884050a(15) =26261498a(16) =100808873a(17) =389101464a(18) =1509198827a(19) =5879305034a(20) =22993849657