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A295637
Maximum k such that there are k nonisomorphic n-vertex trees with the same degree sequence.
1
1, 1, 1, 1, 1, 1, 2, 3, 5, 9, 17, 33, 73, 174, 364, 759, 1859, 4177, 8715, 21053, 49119, 113956, 269059, 711124, 1750732
OFFSET
0,7
EXAMPLE
There are 2 nonisomorphic trees with degree sequence [1, 1, 1, 2, 2, 3]. It is impossible to improve on this, so a(6) = 2. [Stern, p. 39]
PROG
(Sage) # from Max Alekseyev, Jul 22 2024
from collections import Counter
a295637 = lambda n: max( Counter(tuple(sorted(T.degree())) for T in graphs.trees(n)).values() )
CROSSREFS
Sequence in context: A000051 A094373 A213705 * A061902 A166286 A179807
KEYWORD
nonn,more
AUTHOR
Eric M. Schmidt, Nov 25 2017
EXTENSIONS
a(19)-a(24) from Max Alekseyev, Jul 22 2024
STATUS
approved