a(n) = 2*a(n-1) - 6*a(n-2), a(0)=0, a(1)=1.

Terms

a(0) =0a(1) =1a(2) =2a(3) =-2a(4) =-16a(5) =-20a(6) =56a(7) =232a(8) =128a(9) =-1136a(10) =-3040a(11) =736a(12) =19712a(13) =35008a(14) =-48256a(15) =-306560a(16) =-323584a(17) =1192192a(18) =4325888a(19) =1498624a(20) =-22958080a(21) =-54907904a(22) =27932672a(23) =385312768a(24) =603029504a(25) =-1105817600a(26) =-5829812224a(27) =-5024718848a(28) =24929435648a(29) =80007184384