Number of (n+1)X(2+1) 0..1 arrays with every 2X2 subblock sum nondecreasing horizontally, vertically and antidiagonally ne-to-sw.

A253320

Number of (n+1)X(2+1) 0..1 arrays with every 2X2 subblock sum nondecreasing horizontally, vertically and antidiagonally ne-to-sw.

Terms

    a(0) =44a(1) =126a(2) =377a(3) =848a(4) =2042a(5) =4218a(6) =9228a(7) =18482a(8) =38621a(9) =76654a(10) =156631a(11) =310658a(12) =627864a(13) =1247558a(14) =2507954a(15) =4993614a(16) =10012411a(17) =19968402a(18) =39986317a(19) =79836334a(20) =159770246a(21) =319221314a(22) =638635272a(23) =1276539506a(24) =2553459769a(25) =5105272678a(26) =10211298371

External references