Irregular triangle read by rows: for n >= 2, 2 <= k <= floor(n/2) + 1, T(n,k) = the number of semi-meanders with n top arches, a first arch of length one and k arch groupings.
A339179
Irregular triangle read by rows: for n >= 2, 2 <= k <= floor(n/2) + 1, T(n,k) = the number of semi-meanders with n top arches, a first arch of length one and k arch groupings.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =2a(5) =2a(6) =4a(7) =4a(8) =2a(9) =10a(10) =10a(11) =4a(12) =24a(13) =24a(14) =14a(15) =4a(16) =66a(17) =66a(18) =34a(19) =8a(20) =174a(21) =174a(22) =106a(23) =42a(24) =8a(25) =504a(26) =504a(27) =284a(28) =98a(29) =16
External references
- oeis: A339179