Number of nX2 0..2 arrays with rows in nondecreasing lexicographic order and columns in nonincreasing lexicographic order, but with exactly two mistakes.
A278628
Number of nX2 0..2 arrays with rows in nondecreasing lexicographic order and columns in nonincreasing lexicographic order, but with exactly two mistakes.
Terms
- a(0) =0a(1) =13a(2) =285a(3) =3354a(4) =27521a(5) =175881a(6) =932205a(7) =4266912a(8) =17344954a(9) =63898594a(10) =216606040a(11) =683599110a(12) =2027209742a(13) =5691010421a(14) =15216367989a(15) =38944866772a(16) =95817126997a(17) =227430633270a(18) =522402290790
External references
- oeis: A278628