Central coefficients of number triangle A119335.

Terms

a(0) =0a(1) =1a(2) =1a(3) =1a(4) =11a(5) =81a(6) =351a(7) =1149a(8) =3529a(9) =12601a(10) =52724a(11) =222641a(12) =879308a(13) =3295384a(14) =12303201a(15) =47320365a(16) =186738507a(17) =739129809a(18) =2894481813a(19) =11237844615a(20) =43647142533a(21) =170543919327a(22) =669744238998