a(n) = 4*n^2 + 18*n.

Terms

a(0) =0a(1) =22a(2) =52a(3) =90a(4) =136a(5) =190a(6) =252a(7) =322a(8) =400a(9) =486a(10) =580a(11) =682a(12) =792a(13) =910a(14) =1036a(15) =1170a(16) =1312a(17) =1462a(18) =1620a(19) =1786a(20) =1960a(21) =2142a(22) =2332a(23) =2530a(24) =2736a(25) =2950a(26) =3172a(27) =3402a(28) =3640a(29) =3886