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A369177
Number of edges in a graph of n adjacent rectangles in a row with all possible diagonals drawn, as in A306302, but without the rectangles' edges which are perpendicular to the row.
3
6, 24, 66, 152, 318, 576, 998, 1608, 2474, 3600, 5162, 7100, 9670, 12772, 16546, 21036, 26622, 33024, 40814, 49716, 60006, 71560, 85158, 100264, 117626, 136780, 158358, 182080, 209106, 238312, 271314, 307304, 346866, 389488, 436286, 486444, 542026, 601436, 665814, 734504, 809882, 889544
OFFSET
1,1
COMMENTS
See A369175 and A369176 for images of the graph.
FORMULA
a(n) = A369175(n) + A369176(n) - 1 by Euler's formula.
CROSSREFS
Cf. A369175 (regions), A369176 (vertices), A369178 (k-gons), A306302, A331757, A290132, A368757.
Sequence in context: A270851 A092348 A274772 * A234271 A338512 A006528
KEYWORD
nonn
AUTHOR
Scott R. Shannon, Jan 15 2024
STATUS
approved