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A339142 Number of (undirected) cycles in the graph C_5 X P_n. 5
1, 52, 733, 9394, 119235, 1512196, 19177677, 243212478 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..8.

Eric Weisstein's World of Mathematics, Graph Cycle

PROG

(Python)

# Using graphillion

from graphillion import GraphSet

def make_CnXPk(n, k):

    grids = []

    for i in range(1, k + 1):

        for j in range(1, n):

            grids.append((i + (j - 1) * k, i + j * k))

        grids.append((i + (n - 1) * k, i))

    for i in range(1, k * n, k):

        for j in range(1, k):

            grids.append((i + j - 1, i + j))

    return grids

def A339142(n):

    universe = make_CnXPk(5, n)

    GraphSet.set_universe(universe)

    cycles = GraphSet.cycles()

    return cycles.len()

print([A339142(n) for n in range(1, 9)])

CROSSREFS

Cf. A003731 (Hamiltonian cycles), A339117, A339136, A339137, A339140, A339143.

Sequence in context: A249712 A255945 A215365 * A264309 A160344 A163691

Adjacent sequences:  A339139 A339140 A339141 * A339143 A339144 A339145

KEYWORD

nonn,more

AUTHOR

Seiichi Manyama, Nov 25 2020

STATUS

approved

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Last modified September 27 07:30 EDT 2022. Contains 357052 sequences. (Running on oeis4.)