Triangle read by rows: coefficients of third-order hypergeometric-harmonic polynomials.

Terms

a(0) =0a(1) =0a(2) =1a(3) =0a(4) =1a(5) =7a(6) =0a(7) =1a(8) =21a(9) =47a(10) =0a(11) =1a(12) =49a(13) =282a(14) =342a(15) =0a(16) =1a(17) =105a(18) =1175a(19) =3420a(20) =2754a(21) =0a(22) =1a(23) =217a(24) =4230a(25) =22230a(26) =41310a(27) =24552a(28) =0a(29) =1