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A185016
Characteristic function of 6.
15
0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
OFFSET
0,1
COMMENTS
Number of connected 2-regular (simple) graphs with girth exactly 6.
The Euler transformation of this sequence is A079979.
FORMULA
a(n) = A185116(n) - A185117(n).
PROG
(Python)
def A185016(n): return int(n==6) # Chai Wah Wu, Feb 04 2022
CROSSREFS
Characteristic function of g: A000007 (g=0), A063524 (g=1), A185012 (g=2), A185013 (g=3), A185014 (g=4), A185015 (g=5), this sequence (g=6), A185017 (g=7).
Sequence in context: A011710 A135500 A023972 * A103674 A358842 A358758
KEYWORD
nonn,easy
AUTHOR
Jason Kimberley, Sep 30 2011
STATUS
approved