Third accumulation array of Pascal's triangle (as a rectangle), by antidiagonals.

Terms

a(0) =1a(1) =4a(2) =4a(3) =10a(4) =17a(5) =10a(6) =20a(7) =45a(8) =45a(9) =20a(10) =35a(11) =95a(12) =126a(13) =95a(14) =35a(15) =56a(16) =175a(17) =281a(18) =281a(19) =175a(20) =56a(21) =84a(22) =294a(23) =546a(24) =662a(25) =546a(26) =294a(27) =84a(28) =120a(29) =462