Number of (2+1) X (n+1) 0..1 arrays with nondecreasing x(i,j)+x(i,j-1) in the i direction and nondecreasing min(x(i,j),x(i-1,j)) in the j direction.

A250731

Number of (2+1) X (n+1) 0..1 arrays with nondecreasing x(i,j)+x(i,j-1) in the i direction and nondecreasing min(x(i,j),x(i-1,j)) in the j direction.

Terms

    a(0) =18a(1) =46a(2) =110a(3) =257a(4) =596a(5) =1376a(6) =3173a(7) =7310a(8) =16838a(9) =38777a(10) =89300a(11) =205640a(12) =473549a(13) =1090478a(14) =2511134a(15) =5782577a(16) =13315988a(17) =30663728a(18) =70611701a(19) =162602894a(20) =374438006a(21) =862246697a(22) =1985560724a(23) =4572300824a(24) =10528983005a(25) =24245885486a(26) =55832834510

External references