a(n) = 5*a(n-1) - 9*a(n-2) + 8*a(n-3) - 4*a(n-4), with a(0)=0, a(1)=0, a(2)=0, a(3)=1.

Terms

a(0) =0a(1) =0a(2) =0a(3) =1a(4) =5a(5) =16a(6) =43a(7) =107a(8) =256a(9) =597a(10) =1365a(11) =3072a(12) =6827a(13) =15019a(14) =32768a(15) =70997a(16) =152917a(17) =327680a(18) =699051a(19) =1485483a(20) =3145728a(21) =6640981a(22) =13981013a(23) =29360128a(24) =61516459a(25) =128625323a(26) =268435456a(27) =559240533a(28) =1163220309a(29) =2415919104