Maximum second Zagreb index of maximal 3-degenerate graphs with n vertices.

Terms

a(0) =12a(1) =54a(2) =120a(3) =210a(4) =324a(5) =462a(6) =624a(7) =810a(8) =1020a(9) =1254a(10) =1512a(11) =1794a(12) =2100a(13) =2430a(14) =2784a(15) =3162a(16) =3564a(17) =3990a(18) =4440a(19) =4914a(20) =5412a(21) =5934a(22) =6480a(23) =7050a(24) =7644a(25) =8262a(26) =8904a(27) =9570a(28) =10260a(29) =10974