a(n) = (3*n)^5.

Terms

a(0) =0a(1) =243a(2) =7776a(3) =59049a(4) =248832a(5) =759375a(6) =1889568a(7) =4084101a(8) =7962624a(9) =14348907a(10) =24300000a(11) =39135393a(12) =60466176a(13) =90224199a(14) =130691232a(15) =184528125a(16) =254803968a(17) =345025251a(18) =459165024a(19) =601692057a(20) =777600000a(21) =992436543a(22) =1252332576a(23) =1564031349a(24) =1934917632a(25) =2373046875a(26) =2887174368a(27) =3486784401