Number of (2+1) X (n+1) 0..2 arrays with every 2 X 2 subblock diagonal minus antidiagonal sum nondecreasing horizontally, vertically and ne-to-sw antidiagonally.
A253496
Number of (2+1) X (n+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) =414a(1) =1377a(2) =3090a(3) =5386a(4) =9679a(5) =20975a(6) =51167a(7) =133311a(8) =362399a(9) =1014975a(10) =2903327a(11) =8429631a(12) =24731039a(13) =73080255a(14) =217017887a(15) =646610751a(16) =1930949279a(17) =5775084735a(18) =17289730847a(19) =51798148671a(20) =155252361119a(21) =465472916415
External references
- oeis: A253496