a(n) = a(n-1) - 25*a(n-2), a(0)=1, a(1)=5.

Terms

a(0) =1a(1) =5a(2) =-20a(3) =-145a(4) =355a(5) =3980a(6) =-4895a(7) =-104395a(8) =17980a(9) =2627855a(10) =2178355a(11) =-63518020a(12) =-117976895a(13) =1469973605a(14) =4419395980a(15) =-32329944145a(16) =-142814843645a(17) =665433759980