T(2n+1,n+2), T given by A026758.

Terms

a(0) =1a(1) =5a(2) =22a(3) =94a(4) =399a(5) =1696a(6) =7243a(7) =31122a(8) =134623a(9) =586324a(10) =2570936a(11) =11347408a(12) =50401287a(13) =225215350a(14) =1012114200a(15) =4572954259a(16) =20766382311a(17) =94751225278a(18) =434246502792