login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A337417 Number of sets (in the Hausdorff metric geometry) at each location between two sets defined by a complete bipartite graph K(6,n) (with n at least 3) missing two edges, where the removed edges are incident to the same vertex in the six point part. 0
16322, 2145368, 183405386, 13292505200, 895227774482, 58252080636488, 3728244541647386, 236702709858383840, 14969004415531532642, 944809197018309879608, 59577646546802243102186, 3755087128633478474841680, 236623057112566045886497202, 14908882367276213189083986728 (list; graph; refs; listen; history; text; internal format)
OFFSET

3,1

COMMENTS

The Hausdorff metric defines a distance between sets. Using this distance we can define line segments with sets as endpoints. Create two sets from the vertices of the parts A and B (with |A| = 6) of a complete bipartite graph K(6,n) (with n at least 3) missing two edges, where the removed edges are incident to the same point in A. Points in the sets A and B that correspond to vertices that are connected by edges are the same Euclidean distance apart. This sequence tells the number of sets at each location on the line segment between A and B.

Number of {0,1} 6 X n (with n at least 3) matrices with two fixed zero entries in the same row and no zero rows or columns.

Take a complete bipartite graph K(6,n) (with n at least 3) having parts A and B where |A| = 6. This sequence gives the number of edge covers of the graph obtained from this K(6,n) graph after removing two edges, where the two removed edges are incident to the same vertex in A.

REFERENCES

S. Schlicker, R. Vasquez, R. Wofford, Integer Sequences from Configurations in the Hausdorff Metric Geometry via Edge Covers of Bipartite Graphs. In preparation.

LINKS

Table of n, a(n) for n=3..16.

Index entries for linear recurrences with constant coefficients, signature (120,-4593,69688,-428787,978768,-615195).

FORMULA

a(n) = 961*63^(n-2) - 2086*31^(n-2) + 1615*15^(n-2) - 580*7^(n-2) + 95*3^(n-2) - 5.

From Colin Barker, Nov 19 2020: (Start)

G.f.: 2*x^3*(8161 + 93364*x + 464086*x^2 + 43284*x^3 + 172305*x^4) / ((1 - x)*(1 - 3*x)*(1 - 7*x)*(1 - 15*x)*(1 - 31*x)*(1 - 63*x)).

a(n) = 120*a(n-1) - 4593*a(n-2) + 69688*a(n-3) - 428787*a(n-4) + 978768*a(n-5) - 615195*a(n-6) for n>8.

(End)

MAPLE

a:= proc(n) 961*63^(n-2)-2086*31^(n-2)+1615*15^(n-2) - 580*7^(n-2)+95*3^(n-2) -5 end proc: seq(a(n), n=3..20);

PROG

PARI Vec(2*x^3*(8161 + 93364*x + 464086*x^2 + 43284*x^3 + 172305*x^4) / ((1 - x)*(1 - 3*x)*(1 - 7*x)*(1 - 15*x)*(1 - 31*x)*(1 - 63*x)) + O(x^15)) \\ Colin Barker, Nov 19 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: A067375 A237460 A058552 * A013690 A247826 A223109

Adjacent sequences:  A337414 A337415 A337416 * A337418 A337419 A337420

KEYWORD

easy,nonn

AUTHOR

Steven Schlicker, Aug 26 2020

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified November 29 14:50 EST 2021. Contains 349416 sequences. (Running on oeis4.)