a(n) = 1728000*n - 1620240.

Terms

a(0) =107760a(1) =1835760a(2) =3563760a(3) =5291760a(4) =7019760a(5) =8747760a(6) =10475760a(7) =12203760a(8) =13931760a(9) =15659760a(10) =17387760a(11) =19115760a(12) =20843760a(13) =22571760a(14) =24299760a(15) =26027760a(16) =27755760a(17) =29483760a(18) =31211760a(19) =32939760a(20) =34667760a(21) =36395760