Antidiagonal sums of the convolution array A213747.

Terms

a(0) =1a(1) =9a(2) =46a(3) =180a(4) =603a(5) =1827a(6) =5164a(7) =13878a(8) =35905a(9) =90189a(10) =221274a(11) =532584a(12) =1261687a(13) =2949255a(14) =6815896a(15) =15597738a(16) =35389629a(17) =79691985a(18) =178258150a(19) =396361980a(20) =876609811a(21) =1929380139a(22) =4227858756a(23) =9227469150a(24) =20065550713a(25) =43486544277a(26) =93952410034a(27) =202400334288