Number of n X 2 0..1 arrays with rows in nondecreasing lexicographic order and columns in nonincreasing lexicographic order, but with exactly two mistakes.
A278772
Number of n X 2 0..1 arrays with rows in nondecreasing lexicographic order and columns in nonincreasing lexicographic order, but with exactly two mistakes.
Terms
- a(0) =0a(1) =2a(2) =20a(3) =117a(4) =503a(5) =1750a(6) =5209a(7) =13751a(8) =33000a(9) =73282a(10) =152581a(11) =300872a(12) =566293a(13) =1023724a(14) =1786462a(15) =3021818a(16) =4971616a(17) =7978746a(18) =12521114a(19) =19254543a(20) =29066411a(21) =43142066a(22) =63046335a(23) =90822745a(24) =129113400a(25) =181302810a(26) =251689347a(27) =345688410a(28) =470071817
External references
- oeis: A278772