

A303792


Number of connected matchstick graphs on n nodes.


1




OFFSET

1,3


COMMENTS

a(7) >= 209.


LINKS

Table of n, a(n) for n=1..6.
Jaskaran Singh Grover, Changliu Liu, Katia Sycara, Deadlock Analysis and Resolution for MultiRobot Systems, (2020).
Eric Weisstein's World of Mathematics, Connected Graph
Eric Weisstein's World of Mathematics, Matchstick Graph


FORMULA

a(6) = A059103(6)  1.
a(n) <= A059103(n).


EXAMPLE

a(6) is one less than A059103(6) because the 3prism graph Y_3 cannot be drawn in an embedding that is both planar and unitdistance.
There appear to be 13 connected graphs on 7 nodes that are unitdistance but nonmatchstick (including Y_3+e and the Moser spindle).


CROSSREFS

Cf. A059103.
Sequence in context: A269068 A098716 A082938 * A059103 A260709 A112836
Adjacent sequences: A303789 A303790 A303791 * A303793 A303794 A303795


KEYWORD

nonn,hard,more


AUTHOR

Eric W. Weisstein, Apr 30 2018


STATUS

approved



