Maximum length of non-crossing path on n X n square lattice.

Terms

a(0) =1a(1) =4a(2) =10a(3) =21a(4) =34a(5) =53a(6) =74a(7) =101a(8) =130a(9) =165a(10) =202a(11) =245a(12) =290a(13) =341a(14) =394a(15) =453a(16) =514a(17) =581a(18) =650a(19) =725a(20) =802a(21) =885a(22) =970a(23) =1061a(24) =1154a(25) =1253a(26) =1354a(27) =1461a(28) =1570a(29) =1685