Jump Sum Recursion Triangle.

Terms

a(0) =0a(1) =0a(2) =1a(3) =1a(4) =1a(5) =4a(6) =1a(7) =11a(8) =-1a(9) =1a(10) =26a(11) =-27a(12) =1a(13) =57a(14) =-289a(15) =-1a(16) =1a(17) =120a(18) =-2160a(19) =-256a(20) =1a(21) =247a(22) =-13359a(23) =-13604a(24) =1a(25) =1a(26) =502a(27) =-73749a(28) =-383750a(29) =3125