Power floor sequence of 2+sqrt(7).

Terms

a(0) =4a(1) =18a(2) =83a(3) =385a(4) =1788a(5) =8306a(6) =38587a(7) =179265a(8) =832820a(9) =3869074a(10) =17974755a(11) =83506241a(12) =387949228a(13) =1802315634a(14) =8373110219a(15) =38899387777a(16) =180716881764a(17) =839565690386