a(n)=9*a(n-1)-7*a(n-2), a(0)=1, a(1)=7 .

Terms

a(0) =1a(1) =7a(2) =56a(3) =455a(4) =3703a(5) =30142a(6) =245357a(7) =1997219a(8) =16257472a(9) =132336715a(10) =1077228131a(11) =8768696174a(12) =71377668649a(13) =581018144623