OFFSET
0,11
COMMENTS
a(n) is also the number of partitions of n with each part at least 4 and at most n-1. The integer i corresponds to the i-cycle; addition of integers corresponds to disconnected union of cycles.
LINKS
Andrew van den Hoeven, Table of n, a(n) for n = 0..1000
PROG
(Magma) A185224 := func<n|n eq 0 select 0 else #RestrictedPartitions(n, {4..n-1})>;
CROSSREFS
2-regular graphs with girth at least 4: A185114 (connected), this sequence (disconnected), A008484 (not necessarily connected).
Disconnected k-regular simple graphs with girth at least 4: A185214 (any k), A185204 (triangle); specified degree k: A185224 (k=2), A185234 (k=3), A185244 (k=4), A185254 (k=5), A185264 (k=6), A185274 (k=7), A185284 (k=8), A185294 (k=9).
KEYWORD
nonn,easy
AUTHOR
Jason Kimberley, Feb 22 2011
STATUS
approved