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

Terms

a(0) =1a(1) =1a(2) =5a(3) =9a(4) =49a(5) =89a(6) =485a(7) =881a(8) =4801a(9) =8721a(10) =47525a(11) =86329a(12) =470449a(13) =854569a(14) =4656965a(15) =8459361a(16) =46099201a(17) =83739041a(18) =456335045a(19) =828931049a(20) =4517251249a(21) =8205571449a(22) =44716177445a(23) =81226783441a(24) =442644523201a(25) =804062262961