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A164099 Number of planar graphs with n nodes and chromatic number 2. 1
1, 2, 6, 12, 33, 83, 273, 937, 3983, 18871, 103697, 628245, 4161652, 29372754, 218035754 (list; graph; refs; listen; history; text; internal format)
OFFSET
2,2
LINKS
Table of n, a(n) for n=2..16.
FORMULA
(Euler transform of A243321) - 1. - Falk Hüffner, May 10 2019
CROSSREFS
Sequence in context: A217447 A057579 A096610 * A088808 A076278 A221989
Adjacent sequences: A164096 A164097 A164098 * A164100 A164101 A164102
KEYWORD
nonn
AUTHOR
Keith Briggs, Aug 10 2009
EXTENSIONS
Added term 18871 (for n=11), Keith Briggs, Aug 25 2009
a(12)-a(16) from formula by Falk Hüffner, May 10 2019
STATUS
approved

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Last modified June 7 17:50 EDT 2024. Contains 373206 sequences. (Running on oeis4.)