Number of n X 4 0,1 arrays indicating 2 X 2 subblocks of some larger (n+1) X 5 binary array having a sum of three or less, with rows and columns of the latter in lexicographically nondecreasing order.

A227267

Number of n X 4 0,1 arrays indicating 2 X 2 subblocks of some larger (n+1) X 5 binary array having a sum of three or less, with rows and columns of the latter in lexicographically nondecreasing order.

Terms

    a(0) =5a(1) =30a(2) =132a(3) =513a(4) =1949a(5) =7131a(6) =24496a(7) =78761a(8) =238146a(9) =681095a(10) =1852355a(11) =4813290a(12) =11999195a(13) =28801351a(14) =66769946a(15) =149914163a(16) =326768708a(17) =692941231a(18) =1432287640a(19) =2890510485a(20) =5704099317a(21) =11022017108a(22) =20880164204a(23) =38823463828a(24) =70923212058a(25) =127416342458a(26) =225309989754a(27) =392465160179

External references