Number of n X 3 0,1 arrays indicating 2 X 2 subblocks of some larger (n+1) X 4 binary array having a sum of one, with rows and columns of the latter in lexicographically nondecreasing order.
A227382
Number of n X 3 0,1 arrays indicating 2 X 2 subblocks of some larger (n+1) X 4 binary array having a sum of one, with rows and columns of the latter in lexicographically nondecreasing order.
Terms
- a(0) =4a(1) =15a(2) =54a(3) =185a(4) =587a(5) =1704a(6) =4532a(7) =11126a(8) =25430a(9) =54568a(10) =110768a(11) =214130a(12) =396492a(13) =706695a(14) =1217599a(15) =2035257a(16) =3310713a(17) =5254953a(18) =8157605a(19) =12410055a(20) =18533721a(21) =27214306a(22) =39342934a(23) =56065160a(24) =78838936a(25) =109502710a(26) =150354934a(27) =204246360a(28) =274686610
External references
- oeis: A227382