2nd power of rooted tree enumerator; number of linear forests of 2 rooted trees.
1, 2, 5, 12, 30, 74, 188, 478, 1235, 3214, 8450, 22370, 59676, 160140, 432237
2 seqfan posts
Tue Jan 4 05:30:45 CET 2011 [seqfan] Unlabeled super-Catalan - was unlabeled Motzkin