

A101872


Number of Abelian groups of order 2n.


5



1, 2, 1, 3, 1, 2, 1, 5, 2, 2, 1, 3, 1, 2, 1, 7, 1, 4, 1, 3, 1, 2, 1, 5, 2, 2, 3, 3, 1, 2, 1, 11, 1, 2, 1, 6, 1, 2, 1, 5, 1, 2, 1, 3, 2, 2, 1, 7, 2, 4, 1, 3, 1, 6, 1, 5, 1, 2, 1, 3, 1, 2, 2, 15, 1, 2, 1, 3, 1, 2, 1, 10, 1, 2, 2, 3, 1, 2, 1, 7, 5, 2, 1, 3, 1, 2, 1, 5, 1, 4, 1, 3, 1, 2, 1, 11, 1, 4, 2, 6, 1, 2, 1, 5
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OFFSET

1,2


LINKS



FORMULA

Asymptotic mean: Limit_{m>oo} (1/m) * Sum_{k=1..m} a(k) = 2 * (1A048651) * A021002 = 3.26425865613408900779... .  Amiram Eldar, Sep 23 2023


MATHEMATICA

Table[FiniteAbelianGroupCount[2 k], {k, 1, 100}] (* Geoffrey Critzer, Dec 29 2014 *)


PROG



CROSSREFS

Cf. also A101876 (bisection of this sequence).


KEYWORD

nonn,mult,easy


AUTHOR



EXTENSIONS



STATUS

approved



