Sequence with a (1,2) Somos-4 Hankel transform.

Terms

a(0) =1a(1) =0a(2) =-2a(3) =1a(4) =3a(5) =-5a(6) =1a(7) =10a(8) =-24a(9) =18a(10) =52a(11) =-182a(12) =180a(13) =348a(14) =-1474a(15) =1733a(16) =2407a(17) =-12557a(18) =17145a(19) =16561a(20) =-111041a(21) =172625a(22) =107783a(23) =-1006217a(24) =1759149a(25) =592699a(26) =-9265399a(27) =18081483a(28) =1574873a(29) =-86180045