|
| |
|
|
A185226
|
|
Number of disconnected 2-regular 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
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
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 k-regular simple graphs with girth at least g
|
|
|
FORMULA
|
a(n) = A185326(n) - A185116(n).
|
|
|
PROG
|
(Magma) A185226 := func<n|n eq 0 select 0 else #RestrictedPartitions(n, {6..n-1})>;
|
|
|
CROSSREFS
|
Disconnected k-regular simple graphs with girth at least 6: A185216 (all k), A185206 (triangle); this sequence (k=2), A185236 (k=3), A185246 (k=4).
Disconnected 2-regular 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
|
| |
|
|
