0,3

The number of orbits (equivalence classes) to which the square of Vaille's automorphism partitions the set of A000108(n) Dyck paths of semilength n.

a(2n) = 2*A126291(2n) for n>0.

Sequence in context: A097029 A122774 A118841 this_sequence A162724 A140974 A102276

Adjacent sequences: A126291 A126292 A126293 this_sequence A126295 A126296 A126297

nonn

Antti Karttunen (His-Firstname.His-Surname(AT)gmail.com), Jan 02 2007