paths problem

paths.jl

const NEIG_py = [[1, 4, 5], [0, 2, 4, 5, 6], [1, 3, 5, 6, 7], [2, 6, 7], [0, 1, 5, 8, 9], [0, 1, 2, 4, 6, 8, 9, 10], [1, 2, 3, 5, 7, 9, 10, 11], [2, 3, 6, 10, 11], [4, 5, 9, 12, 13], [4, 5, 6, 8, 10, 12, 13, 14], [5, 6, 7, 9, 11, 13, 14, 15], [6, 7, 10, 14, 15], [8, 9, 13], [8, 9, 10, 12, 14], [9, 10, 11, 13, 15], [10, 11, 14]];
const NEIG = [n.+1 for n in NEIG_py]
function enlarge(path::Vector{Int})
    (push!(copy(path),loc) for loc in NEIG[path[end]] if !(loc in path))
end
collect(enlarge([1]))
function enlargepaths(paths)
    Iterators.Flatten(enlarge(path) for path in paths)
end
collect(enlargepaths([[1],[2]]))
function paths(targetlen)
    paths = ([i] for i=1:16)
    for newlen in 2:targetlen
        paths = enlargepaths(paths)
    end
    paths
end
p = sum(1 for path in paths(10))