a(n) = 531441*n - 313146.

Terms

a(0) =218295a(1) =749736a(2) =1281177a(3) =1812618a(4) =2344059a(5) =2875500a(6) =3406941a(7) =3938382a(8) =4469823a(9) =5001264a(10) =5532705a(11) =6064146a(12) =6595587a(13) =7127028a(14) =7658469a(15) =8189910a(16) =8721351a(17) =9252792a(18) =9784233a(19) =10315674a(20) =10847115a(21) =11378556a(22) =11909997a(23) =12441438a(24) =12972879