Boustrophedon transform of odd numbers.

Terms

a(0) =1a(1) =4a(2) =12a(3) =33a(4) =96a(5) =317a(6) =1218a(7) =5425a(8) =27608a(9) =158129a(10) =1006574a(11) =7048657a(12) =53847420a(13) =445643681a(14) =3971876930a(15) =37928628529a(16) =386337833232