Rectangular array T(n,k) = binomial(n+1,2)*(n^k - (n-1)^k) read by antidiagonals.

Terms

a(0) =1a(1) =1a(2) =3a(3) =1a(4) =9a(5) =6a(6) =1a(7) =21a(8) =30a(9) =10a(10) =1a(11) =45a(12) =114a(13) =70a(14) =15a(15) =1a(16) =93a(17) =390a(18) =370a(19) =135a(20) =21a(21) =1a(22) =189a(23) =1266a(24) =1750a(25) =915a(26) =231a(27) =28a(28) =1a(29) =381