A333606 Number of directed Hamiltonian walks from NW to SW corners of a 10 X n grid.

1, 1, 256, 1480, 117852, 1513468, 71154709, 1283569420, 47001928863, 1013346943033, 32440676063382, 771708613086275, 22928865477892898, 576390471202016758, 16424125813587374688, 425923820730159849603, 11854446538789342310672, 312866945593394069370317

Offset: 1

Author

Seiichi Manyama, Mar 28 2020

Keywords

• nonn

Links

• Ed Wynn, Table of n, a(n) for n = 1..68

Crossrefs

Row n=10 of A271592.

Cf. A333585.

Programs

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 A333606(n):
    return A271592(10, n)
print([A333606(n) for n in range(1, 8)])

Extensions

More terms from Ed Wynn, Jun 28 2023