Number of paths from (0,0) to (n,n) avoiding 3 or more consecutive east steps and 3 or more consecutive north steps.

A177790

Number of paths from (0,0) to (n,n) avoiding 3 or more consecutive east steps and 3 or more consecutive north steps.

Terms

    a(0) =1a(1) =2a(2) =6a(3) =14a(4) =34a(5) =84a(6) =208a(7) =518a(8) =1296a(9) =3254a(10) =8196a(11) =20700a(12) =52404a(13) =132942a(14) =337878a(15) =860142a(16) =2192902a(17) =5598144a(18) =14308378a(19) =36610970a(20) =93770358a(21) =240390602a(22) =616787116a(23) =1583765724a(24) =4069672444a(25) =10464501074a(26) =26924530158a(27) =69315481778a(28) =178545361842a(29) =460138256784

External references