Triangle A124029 with the (0,0) entry replaced by 4.

Terms

a(0) =4a(1) =4a(2) =-1a(3) =15a(4) =-8a(5) =1a(6) =56a(7) =-46a(8) =12a(9) =-1a(10) =209a(11) =-232a(12) =93a(13) =-16a(14) =1a(15) =780a(16) =-1091a(17) =592a(18) =-156a(19) =20a(20) =-1a(21) =2911a(22) =-4912a(23) =3366a(24) =-1200a(25) =235a(26) =-24a(27) =1a(28) =10864a(29) =-21468