

A276032


Number of refinements of the partition n^1 with all numbers taken modulo 2.


1



1, 2, 3, 7, 8, 21, 22, 63, 64, 195, 196, 624, 625, 2054, 2055, 6916, 6917, 23712, 23713, 82498, 82499, 290510, 290511, 1033410, 1033411, 3707850, 3707851, 13402695, 13402696, 48760365, 48760366, 178405155, 178405156, 656043855, 656043856, 2423307045
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OFFSET

1,2


COMMENTS

Consider the ranked poset L(n) of partitions defined in A002846, and take the elements of each node modulo 2, collapsing two equivalent nodes into 1. Then a(n) is the total number of paths of all lengths 0,1,...,n1 that start at (n mod 2)^1 and end at any node in the poset.
Oddindexed terms are the partial sums of Catalan numbers: A014138.
Evenindexed terms are one less than the following oddindexed term.
Originally this entry had a reference to a paper on the arXiv by Caleb Ji, Enumerative Properties of Posets Corresponding to a Certain Class of No Strategy Games, arXiv:1608.06025 [math.CO], 2016. However, this article has since been removed from the arXiv.  N. J. A. Sloane, Sep 07 2018


LINKS

Table of n, a(n) for n=1..36.


CROSSREFS

Cf. A276033, A014138.
Sequence in context: A247843 A181658 A251541 * A114281 A137823 A024540
Adjacent sequences: A276029 A276030 A276031 * A276033 A276034 A276035


KEYWORD

nonn


AUTHOR

Caleb Ji, Aug 17 2016


STATUS

approved



