OFFSET
0,11
COMMENTS
Bridges are disallowed.
LINKS
Andrew Howroyd, Table of n, a(n) for n = 0..200
Wikipedia, Cactus graph
EXAMPLE
a(6) = 1 corresponding with a hexagon.
a(7) = 1 corresponding with two quadrilaterals joined at a node.
PROG
(PARI) \\ See A332650 for UCacti.
seq(n)={concat([1], UCacti(vector(n, i, i>2&&i%2==0)))}
CROSSREFS
KEYWORD
nonn
AUTHOR
Andrew Howroyd, Feb 18 2020
STATUS
approved