a(n) = (10*n + 7)^2.

Terms

a(0) =49a(1) =289a(2) =729a(3) =1369a(4) =2209a(5) =3249a(6) =4489a(7) =5929a(8) =7569a(9) =9409a(10) =11449a(11) =13689a(12) =16129a(13) =18769a(14) =21609a(15) =24649a(16) =27889a(17) =31329a(18) =34969a(19) =38809a(20) =42849a(21) =47089a(22) =51529a(23) =56169a(24) =61009a(25) =66049a(26) =71289a(27) =76729a(28) =82369a(29) =88209