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A335610 Number of sets (in the Hausdorff metric geometry) at each location between two sets defined by a K(5,n) (with n at least 2) complete bipartite graph missing one edge. 0
80, 6800, 316928, 11784608, 397551920, 12828154160, 405380093408, 12683426301248, 394943123789840, 12269641330477520, 380755304897252288, 11809363300986469088, 366179512530595589360, 11352903763691009133680, 351960100658771425777568, 10911064386177197162304128 (list; graph; refs; listen; history; text; internal format)
OFFSET
2,1
COMMENTS
Number of {0,1} 5 X n matrices (with n at least 2) with one fixed zero entry and no zero rows or columns.
Number of edge covers of a K(5,n) complete bipartite graph (with n at least 2) missing one edge.
LINKS
Steven Schlicker, Roman Vasquez, and Rachel Wofford, Integer Sequences from Configurations in the Hausdorff Metric Geometry via Edge Covers of Bipartite Graphs, J. Int. Seq. (2023) Vol. 26, Art. 23.6.6.
FORMULA
a(n) = 15*31^(n-1) - 43*15^(n-1) + 46*7^(n-1) - 22*3^(n-1) + 4.
From Stefano Spezia, Jul 04 2020: (Start)
G.f.: 16*x^2*(5 + 140*x + 593*x^2 + 522*x^3)/(1 - 57*x + 1002*x^2 - 6562*x^3 + 15381*x^4 - 9765*x^5).
a(n) = 57*a(n-1) - 1002*a(n-2) + 6562*a(n-3) - 15381*a(n-4) + 9765*a(n-5) for n > 6. (End)
EXAMPLE
For n = 2, a(2) = 80.
MATHEMATICA
Array[15*31^(# - 1) - 43*15^(# - 1) + 46*7^(# - 1) - 22*3^(# - 1) + 4 &, 16, 2] (* Michael De Vlieger, Jun 22 2020 *)
CROSSREFS
Sequences of segments from removing edges from bipartite graphs A335608-A335613, A337416-A337418, A340173-A340175, A340199-A340201, A340897-A340899, A342580, A342796, A342850, A340403-A340405, A340433-A340438, A341551-A341553, A342327-A342328, A343372-A343374, A343800. Polygonal chain sequences A152927, A152928, A152929, A152930, A152931, A152932, A152933, A152934, A152939. Number of {0,1} n X n matrices with no zero rows or columns A048291.
Sequence in context: A216987 A283102 A259076 * A190931 A006202 A278736
KEYWORD
easy,nonn
AUTHOR
Steven Schlicker, Jun 15 2020
STATUS
approved

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Last modified June 6 14:21 EDT 2024. Contains 373128 sequences. (Running on oeis4.)