a(n) = 531441*n^2 - 740664*n + 258065.

Terms

a(0) =48842a(1) =902501a(2) =2819042a(3) =5798465a(4) =9840770a(5) =14945957a(6) =21114026a(7) =28344977a(8) =36638810a(9) =45995525a(10) =56415122a(11) =67897601a(12) =80442962a(13) =94051205a(14) =108722330a(15) =124456337a(16) =141253226a(17) =159112997a(18) =178035650a(19) =198021185a(20) =219069602a(21) =241180901