Number of (n+1) X 5 0..2 arrays with all 2 X 2 subblock sums the same.

Terms

a(0) =855a(1) =1233a(2) =1887a(3) =3309a(4) =6111a(5) =12525a(6) =26655a(7) =61125a(8) =144495a(9) =361293a(10) =925647a(11) =2471829a(12) =6713631a(13) =18762045a(14) =52968255a(15) =152326725a(16) =440454735a(17) =1288454253a(18) =3779340207a(19) =11166335349a(20) =33034529151a(21) =98175588765a(22) =291944589855a(23) =870672034725