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A333604
Number of directed Hamiltonian walks from NW to SW corners of an 8 X n grid.
2
1, 1, 64, 264, 6820, 52387, 909009, 8934966, 130373192, 1440623260, 19338414411, 226336038320, 2916455246831, 35119270968805, 443497762883269, 5416278334971240, 67721300861621626, 832844111255909543, 10362230473284966919
OFFSET
1,3
PROG
(Python)
# Using graphillion
from graphillion import GraphSet
import graphillion.tutorial as tl
def A271592(n, k):
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()
def A333604(n):
return A271592(8, n)
print([A333604(n) for n in range(1, 9)])
CROSSREFS
Row n=8 of A271592.
Cf. A333583.
Sequence in context: A255662 A045029 A231528 * A259406 A029873 A218069
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Mar 28 2020
EXTENSIONS
More terms from Ed Wynn, Jun 25 2023
STATUS
approved