Partial sums of floor(3^n/10)/2.

Terms

a(0) =0a(1) =0a(2) =1a(3) =5a(4) =17a(5) =53a(6) =162a(7) =490a(8) =1474a(9) =4426a(10) =13283a(11) =39855a(12) =119571a(13) =358719a(14) =1076164a(15) =3228500a(16) =9685508a(17) =29056532a(18) =87169605a(19) =261508825a(20) =784526485a(21) =2353579465a(22) =7060738406a(23) =21182215230a(24) =63546645702