Number of different fixed (possibly) disconnected trominoes bounded tightly by an n X n square.

Terms

a(0) =0a(1) =4a(2) =22a(3) =52a(4) =94a(5) =148a(6) =214a(7) =292a(8) =382a(9) =484a(10) =598a(11) =724a(12) =862a(13) =1012a(14) =1174a(15) =1348a(16) =1534a(17) =1732a(18) =1942a(19) =2164a(20) =2398a(21) =2644a(22) =2902a(23) =3172a(24) =3454a(25) =3748a(26) =4054a(27) =4372a(28) =4702a(29) =5044