a(n) = a(n-1) + 9*a(n-2) - 9*a(n-3), where a(0) = 1, a(1) = 3, a(2) = 6, a(3) = 33.

A297444

a(n) = a(n-1) + 9*a(n-2) - 9*a(n-3), where a(0) = 1, a(1) = 3, a(2) = 6, a(3) = 33.

Terms

    a(0) =1a(1) =3a(2) =6a(3) =33a(4) =60a(5) =303a(6) =546a(7) =2733a(8) =4920a(9) =24603a(10) =44286a(11) =221433a(12) =398580a(13) =1992903a(14) =3587226a(15) =17936133a(16) =32285040a(17) =161425203a(18) =290565366a(19) =1452826833a(20) =2615088300a(21) =13075441503a(22) =23535794706a(23) =117678973533a(24) =211822152360

External references