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A291594 Number of (non-null) connected induced subgraphs in the n-triangular honeycomb acute knight graph. 0
1, 3, 9, 25, 69, 219, 832, 3894, 23202, 176838 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..10.

Eric Weisstein's World of Mathematics, Connected Graph

Eric Weisstein's World of Mathematics, Vertex-Induced Subgraph

MATHEMATICA

Table[With[{g = GraphData[{"TriangularHoneycombAcuteKnight", n}]}, Count[Subgraph[g, #] & /@ Rest[Subsets[VertexList[g]]], _?ConnectedGraphQ]], {n, 5}]

Table[With[{g = GraphData[{"TriangularHoneycombAcuteKnight", n}]}, Total[Boole[ConnectedGraphQ[Subgraph[g, #]]] & /@ Rest[Subsets[VertexList[g]]]]], {n, 5}]

CROSSREFS

Sequence in context: A211297 A297590 A244934 * A007046 A211286 A211285

Adjacent sequences:  A291591 A291592 A291593 * A291595 A291596 A291597

KEYWORD

nonn,more

AUTHOR

Eric W. Weisstein, Aug 27 2017

EXTENSIONS

a(7)-a(10) from Andrew Howroyd, Aug 27 2017

STATUS

approved

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Last modified December 8 07:52 EST 2021. Contains 349593 sequences. (Running on oeis4.)