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A333606
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Number of directed Hamiltonian walks from NW to SW corners of a 10 X n grid.
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2
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1, 1, 256, 1480, 117852, 1513468, 71154709, 1283569420, 47001928863, 1013346943033, 32440676063382, 771708613086275, 22928865477892898, 576390471202016758, 16424125813587374688, 425923820730159849603, 11854446538789342310672, 312866945593394069370317
(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([A333606(n) for n in range(1, 8)])
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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 28 2023
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STATUS
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approved
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