a(n) = 676*n^2 - 2*n.

Terms

a(0) =674a(1) =2700a(2) =6078a(3) =10808a(4) =16890a(5) =24324a(6) =33110a(7) =43248a(8) =54738a(9) =67580a(10) =81774a(11) =97320a(12) =114218a(13) =132468a(14) =152070a(15) =173024a(16) =195330a(17) =218988a(18) =243998a(19) =270360a(20) =298074a(21) =327140a(22) =357558a(23) =389328a(24) =422450a(25) =456924a(26) =492750a(27) =529928a(28) =568458a(29) =608340