Number of (n+1) X (3+1) 0..2 arrays with every 2 X 2 subblock diagonal minus antidiagonal sum nondecreasing horizontally, vertically and ne-to-sw antidiagonally.
A253490
Number of (n+1) X (3+1) 0..2 arrays with every 2 X 2 subblock diagonal minus antidiagonal sum nondecreasing horizontally, vertically and ne-to-sw antidiagonally.
Terms
- a(0) =1388a(1) =3090a(2) =4196a(3) =6931a(4) =13528a(5) =29370a(6) =68992a(7) =172050a(8) =449608a(9) =1219050a(10) =3400912a(11) =9693570a(12) =28065688a(13) =82170330a(14) =242460832a(15) =719285490a(16) =2141665768a(17) =6392619210a(18) =19113104752a(19) =57209811810a(20) =171370433848a(21) =513593301690
External references
- oeis: A253490