Number of (n+1) X (1+1) 0..2 arrays with every 2 X 2 subblock ne-sw antidiagonal difference nondecreasing horizontally and nw+se diagonal sum nondecreasing vertically.
A253742
Number of (n+1) X (1+1) 0..2 arrays with every 2 X 2 subblock ne-sw antidiagonal difference nondecreasing horizontally and nw+se diagonal sum nondecreasing vertically.
Terms
- a(0) =81a(1) =450a(2) =1998a(3) =7803a(4) =28107a(5) =95940a(6) =315576a(7) =1011357a(8) =3181653a(9) =9876870a(10) =30368034a(11) =92726271a(12) =281717919a(13) =852821640a(14) =2574980172a(15) =7760330145a(16) =23356488105a(17) =70229896650a(18) =211029428790a(19) =633805512579
External references
- oeis: A253742