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A243302
Consider a triangular Go board graph with side length n; remove i nodes and let j be the number of nodes in the largest connected subgraph remaining; then a(n) = minimum (i + j).
2
1, 3, 4, 6, 9, 11, 14, 18, 21, 25
OFFSET
1,2
COMMENTS
Maximum number of boat shapes formed from six equilateral triangles that can be placed in an equilateral triangle of order a(n+4). - Craig Knecht, Sep 13 2017
EXAMPLE
a(11) <= 29 because i = 20 and j = 9 in the following graph:
-
- -
- - -
X - - X
- X - X -
- - X X - -
- - X - X - -
X X X - - X X X
- - - X - X - - -
- - - X - - X - - -
- - - X - - - X - - -
a(11) <= 29 because i = 16 and j = 13 in the following graph:
-
- -
- - -
- - - -
X X - - -
- - X X X X
- - X - X - -
- - X - - X - -
- - X - - - X - -
- - X - - - X - - -
- - X - - - X - - - -
CROSSREFS
For square graphs see A243205.
Cf. A301654.
Sequence in context: A285412 A105527 A094345 * A301654 A289233 A039889
KEYWORD
nonn,more
AUTHOR
Gordon Hamilton, Jun 03 2014
STATUS
approved