A285765 - OEIS

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A285765

Number of connected induced (non-null) subgraphs of the n X n queen graph.

1, 15, 495, 64815, 33478163, 68694593248

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

LINKS

Table of n, a(n) for n=1..6.

Eric Weisstein's World of Mathematics, Queen Graph

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

MATHEMATICA

Table[g = GraphData[{"Queen", {n, n}}]; -1 + ParallelSum[ Boole@ ConnectedGraphQ@ Subgraph[g, s], {s, Subsets@ Range[n^2]}], {n, 4}]

CROSSREFS

Cf. A020873 (wheel), A059020 (ladder), A059525 (grid), A286139 (king), A286182 (prism), A286183 (antiprism), A286184 (helm), A286185 (Möbius ladder), A286186 (friendship), A286187 (web), A286188 (gear), A286189 (rook).

Sequence in context: A151816 A013431 A013432 * A287070 A062752 A218226

Adjacent sequences: A285762 A285763 A285764 * A285766 A285767 A285768

KEYWORD

nonn,more

AUTHOR

Giovanni Resta, May 04 2017

STATUS

approved