a(n) = n^6 - n^5 + n^4 - n^3 + n^2 - n + 1.

Terms

a(0) =1a(1) =1a(2) =43a(3) =547a(4) =3277a(5) =13021a(6) =39991a(7) =102943a(8) =233017a(9) =478297a(10) =909091a(11) =1623931a(12) =2756293a(13) =4482037a(14) =7027567a(15) =10678711a(16) =15790321a(17) =22796593a(18) =32222107a(19) =44693587a(20) =60952381a(21) =81867661a(22) =108450343a(23) =141867727a(24) =183458857a(25) =234750601a(26) =297474451a(27) =373584043a(28) =465273397a(29) =574995877