T(2n+5,n), array T as in A055794.

Terms

a(0) =1a(1) =7a(2) =29a(3) =93a(4) =255a(5) =627a(6) =1419a(7) =3003a(8) =6006a(9) =11440a(10) =20878a(11) =36686a(12) =62322a(13) =102714a(14) =164730a(15) =257754a(16) =394383a(17) =591261a(18) =870067a(19) =1258675a(20) =1792505a(21) =2516085a(22) =3484845a(23) =4767165a(24) =6446700a(25) =8625006a(26) =11424492a(27) =14991724a(28) =19501108a(29) =25158980