Number of nX3 0,1 arrays indicating 2X2 subblocks of some larger (n+1)X4 binary array having a sum of two or less, with rows and columns of the latter in lexicographically nondecreasing order.
A227260
Number of nX3 0,1 arrays indicating 2X2 subblocks of some larger (n+1)X4 binary array having a sum of two or less, with rows and columns of the latter in lexicographically nondecreasing order.
Terms
- a(0) =4a(1) =23a(2) =98a(3) =353a(4) =1111a(5) =3136a(6) =8065a(7) =19146a(8) =42385a(9) =88282a(10) =174361a(11) =328741a(12) =595043a(13) =1038979a(14) =1757024a(15) =2887631a(16) =4625512a(17) =7239575a(18) =11095178a(19) =16681436a(20) =24644396a(21) =35826978a(22) =51316667a(23) =72502032a(24) =101139243a(25) =139429856a(26) =190111239a(27) =256561119
External references
- oeis: A227260