Triangle: T(n,k)=C(4n+1,2k), 0<=k<=n.

Terms

a(0) =1a(1) =1a(2) =10a(3) =1a(4) =36a(5) =126a(6) =1a(7) =78a(8) =715a(9) =1716a(10) =1a(11) =136a(12) =2380a(13) =12376a(14) =24310a(15) =1a(16) =210a(17) =5985a(18) =54264a(19) =203490a(20) =352716a(21) =1a(22) =300a(23) =12650a(24) =177100a(25) =1081575a(26) =3268760a(27) =5200300a(28) =1a(29) =406