A088976 Breadth-first traversal of the Collatz tree, with the even child of each node traversed prior to its odd child. If the Collatz 3n+1 conjecture is true, this is a permutation of all positive integers.

1, 2, 4, 8, 16, 32, 5, 64, 10, 128, 21, 20, 3, 256, 42, 40, 6, 512, 85, 84, 80, 13, 12, 1024, 170, 168, 160, 26, 24, 2048, 341, 340, 336, 320, 53, 52, 48, 4096, 682, 680, 113, 672, 640, 106, 104, 17, 96, 8192, 1365, 1364, 227, 1360, 226, 1344, 1280, 213, 212, 35, 208

Offset

0,2

Links

T. D. Noe, Table of n, a(n) for n = 0..3517

Prog

(Python)
def A088976():
    yield 1
    for x in A088976():
        yield 2*x
        if x > 4 and x % 6 == 4:
            yield (x - 1)//3
a = A088976(); print([next(a) for _ in range(100)])

Crossrefs

Cf. A127824 (terms at the same depth are sorted).

Sequence in context: A114183 A036129 A319303 * A016020 A364628 A328753

Adjacent sequences: A088973 A088974 A088975 * A088977 A088978 A088979

Keyword

easy,nonn

Author

David Eppstein, Oct 31 2003

Status

approved