Number of n X 6 nonnegative integer arrays with upper left 0 and every value within 2 of its city block distance from the upper left and every value increasing by 0 or 1 with every step right or down.

A252818

Number of n X 6 nonnegative integer arrays with upper left 0 and every value within 2 of its city block distance from the upper left and every value increasing by 0 or 1 with every step right or down.

Terms

    a(0) =16a(1) =147a(2) =1032a(3) =5490a(4) =23664a(5) =86724a(6) =279300a(7) =809349a(8) =2147638a(9) =5289321a(10) =12219498a(11) =26705926a(12) =55598468a(13) =110890224a(14) =212893984a(15) =395014703a(16) =710759820a(17) =1243830839a(18) =2122388828a(19) =3538891338a(20) =5777267504a(21) =9249641452a(22) =14545342212a(23) =22495562705

External references