Number of sequences of n pairs of balanced brackets of three types, round, square, and angle, such that no square brackets are allowed inside matching round brackets.
A165976
Number of sequences of n pairs of balanced brackets of three types, round, square, and angle, such that no square brackets are allowed inside matching round brackets.
Terms
- a(0) =1a(1) =3a(2) =17a(3) =117a(4) =887a(5) =7131a(6) =59661a(7) =513897a(8) =4526603a(9) =40588263a(10) =369277481a(11) =3400840845a(12) =31644776383a(13) =297079014771
External references
- oeis: A165976