A331114 Number of rooted trees with 2-colored non-root nodes with an n nodes of each color.

1, 3, 37, 596, 11513, 245356, 5597060, 133950215, 3323281496, 84787933926, 2212123329500, 58779046239904, 1585796125188065, 43337540217740908, 1197492197496481744, 33406620056723507124, 939775084670916268134, 26632926871927867655261, 759732892913483065912296

Offset

0,2

Comments

The total number of nodes including the root is 2n + 1.

Links

Andrew Howroyd, Table of n, a(n) for n = 0..100

Formula

a(n) = A304489(2*n+1, n).

Example

a(1) = 3 because there are three trees with one root node and one additional node of each color:
   1 -- o -- 2,
   o -- 1 -- 2,
   o -- 2 -- 1.

Crossrefs

Cf. A304489, A329055, A331113.

Sequence in context: A216696 A362724 A333385 * A245265 A362672 A143639

Adjacent sequences: A331111 A331112 A331113 * A331115 A331116 A331117

Keyword

nonn

Author

Andrew Howroyd, Jan 09 2020

Status

approved