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A333604
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Number of directed Hamiltonian walks from NW to SW corners of an 8 X n grid.
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2
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1, 1, 64, 264, 6820, 52387, 909009, 8934966, 130373192, 1440623260, 19338414411, 226336038320, 2916455246831, 35119270968805, 443497762883269, 5416278334971240, 67721300861621626, 832844111255909543, 10362230473284966919
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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1,3
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LINKS
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PROG
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(Python)
# Using graphillion
from graphillion import GraphSet
import graphillion.tutorial as tl
if k == 1: return 1
universe = tl.grid(k - 1, n - 1)
GraphSet.set_universe(universe)
start, goal = 1, n
paths = GraphSet.paths(start, goal, is_hamilton=True)
return paths.len()
print([A333604(n) for n in range(1, 9)])
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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More terms from Ed Wynn, Jun 25 2023
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STATUS
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approved
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