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A333583
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Number of Hamiltonian paths in an 8 X (2n+1) grid starting at the lower left corner and finishing in the upper right corner.
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3
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1, 64, 6706, 851073, 114243216, 15695570146, 2178079125340, 303568139329711, 42388918310108440, 5923750747499881068, 828111786035239457647, 115782566867663040724929, 16189114623816733581826838, 2263672174616450290622937801, 316525123224847580237219904819
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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0,2
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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 n == 1 or k == 1: return 1
universe = tl.grid(n - 1, k - 1)
GraphSet.set_universe(universe)
start, goal = 1, k * n
paths = GraphSet.paths(start, goal, is_hamilton=True)
return paths.len()
print([A333583(n) for n in range(7)])
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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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STATUS
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approved
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