a(n) = 5*a(n-1) + 10*a(n-2), with a(1)=0 and a(2)=1.

A180250

a(n) = 5*a(n-1) + 10*a(n-2), with a(1)=0 and a(2)=1.

Terms

    a(0) =0a(1) =1a(2) =5a(3) =35a(4) =225a(5) =1475a(6) =9625a(7) =62875a(8) =410625a(9) =2681875a(10) =17515625a(11) =114396875a(12) =747140625a(13) =4879671875a(14) =31869765625a(15) =208145546875

External references