If n mod 3 = 0 then a(n) = 3^(n/3) + 12*n, if n mod 3 = 1 then a(n) = 4*3^((n-4)/3) + 12*n + 51, otherwise a(n) = 2*3^((n-2)/3) + 12*n - 36.

A276401

If n mod 3 = 0 then a(n) = 3^(n/3) + 12*n, if n mod 3 = 1 then a(n) = 4*3^((n-4)/3) + 12*n + 51, otherwise a(n) = 2*3^((n-2)/3) + 12*n - 36.

Terms

    a(0) =39a(1) =103a(2) =30a(3) =81a(4) =147a(5) =78a(6) =135a(7) =207a(8) =150a(9) =225a(10) =315a(11) =294a(12) =423a(13) =567a(14) =654a(15) =945a(16) =1251a(17) =1662a(18) =2439a(19) =3231a(20) =4614a(21) =6849a(22) =9099a(23) =13398a(24) =20007a(25) =26631a(26) =39678a(27) =59409a(28) =79155a(29) =118446

External references