Number of rotationally symmetric closed meanders of length 4n+2.

A060206

Number of rotationally symmetric closed meanders of length 4n+2.

Terms

    a(0) =1a(1) =2a(2) =10a(3) =66a(4) =504a(5) =4210a(6) =37378a(7) =346846a(8) =3328188a(9) =32786630a(10) =329903058a(11) =3377919260a(12) =35095839848a(13) =369192702554

External references