Harary index of the n X n bishop graph.

Terms

a(0) =0a(1) =2a(2) =13a(3) =42a(4) =102a(5) =208a(6) =379a(7) =636a(8) =1004a(9) =1510a(10) =2185a(11) =3062a(12) =4178a(13) =5572a(14) =7287a(15) =9368a(16) =11864a(17) =14826a(18) =18309a(19) =22370a(20) =27070a(21) =32472a(22) =38643a(23) =45652a(24) =53572a(25) =62478a(26) =72449a(27) =83566a(28) =95914a(29) =109580