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URL: https://oeis.org/A273725

⇱ A273725 - OEIS

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A273725
Number of quaternary heaps on n levels (i.e., of (4^n-1)/3 elements).
3
1, 1, 24, 3892643213082624
OFFSET
0,3
COMMENTS
a(n) is also the number of labeled histories for a fully symmetric quadfurcating labeled topology with 4^n leaves. - Noah A Rosenberg, Feb 24 2025
LINKS
E. H. Dickey, N. A. Rosenberg, Labelled histories with multifurcation and simultaneity, Phil. Trans. R. Soc. B 380 (2025), 20230307.
Wikipedia, D-ary heap
FORMULA
a(n) = A178009(A002450(n)).
CROSSREFS
Column k=4 of A273712.
Sequence in context: A297424 A013910 A007458 * A072244 A067669 A068741
KEYWORD
nonn
AUTHOR
Alois P. Heinz, May 28 2016
STATUS
approved