Number of (n+1) X 2 0..2 arrays with the number of clockwise edge increases in 2 X 2 subblocks nondecreasing, and counterclockwise edge increases nonincreasing, rightwards and downwards.

A206535

Number of (n+1) X 2 0..2 arrays with the number of clockwise edge increases in 2 X 2 subblocks nondecreasing, and counterclockwise edge increases nonincreasing, rightwards and downwards.

Terms

    a(0) =81a(1) =399a(2) =1620a(3) =6462a(4) =26481a(5) =110769a(6) =469617a(7) =2009553a(8) =8655441a(9) =37451697a(10) =162572721a(11) =707284113a(12) =3081856785a(13) =13442980209a(14) =58681197681a(15) =256284824145

External references