

A185226


Number of disconnected 2regular simple graphs on n vertices with girth at least 6.


13



0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 5, 5, 7, 8, 10, 11, 15, 16, 20, 23, 28, 31, 39, 43, 52, 59, 70, 79, 95, 106, 125, 142, 166, 187, 220, 247, 287, 325, 375, 423, 490, 551, 633, 715, 818, 921, 1055, 1186, 1352, 1522, 1729, 1943, 2208
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OFFSET

0,15


COMMENTS

Number of partitions of n with each part at least 6, and at least 2 parts.


LINKS

Table of n, a(n) for n=0..60.
Jason Kimberley, Disconnected regular graphs with girth at least 6
Jason Kimberley, Index of sequences counting disconnected kregular simple graphs with girth at least g


FORMULA

a(n) = A185326(n)  A185116(n).


PROG

(Magma) A185226 := func<nn eq 0 select 0 else #RestrictedPartitions(n, {6..n1})>;


CROSSREFS

Disconnected kregular simple graphs with girth at least 6: A185216 (all k), A185206 (triangle); this sequence (k=2), A185236 (k=3), A185246 (k=4).
Disconnected 2regular simple graphs with girth at least g: A165652 (g=3), A185224 (g=4), A185225 (g=5), this sequence (g=6), A185227 (g=7), A185228 (g=8), A185229 (g=9).
Sequence in context: A239513 A029018 A238217 * A096765 A025147 A032230
Adjacent sequences: A185223 A185224 A185225 * A185227 A185228 A185229


KEYWORD

nonn,easy


AUTHOR

Jason Kimberley, Feb 22 2011


STATUS

approved



