Number of (n+1) X (3+1) 0..1 arrays with every 2 X 2 subblock diagonal minimum minus antidiagonal minimum nondecreasing horizontally and diagonal maximum minus antidiagonal maximum nondecreasing vertically.

A253226

Number of (n+1) X (3+1) 0..1 arrays with every 2 X 2 subblock diagonal minimum minus antidiagonal minimum nondecreasing horizontally and diagonal maximum minus antidiagonal maximum nondecreasing vertically.

Terms

    a(0) =125a(1) =306a(2) =494a(3) =914a(4) =1709a(5) =3241a(6) =6231a(7) =12122a(8) =23800a(9) =47037a(10) =93377a(11) =185908a(12) =370806a(13) =740423a(14) =1479463a(15) =2957334a(16) =5912852a(17) =11823649a(18) =23644989a(19) =47287400a(20) =94571938a(21) =189140715a(22) =378277955a(23) =756552106a(24) =1513100064a(25) =3026195621a(26) =6052386361

External references