A094451 a(n) = A033485(n) modulo 3.

1, 2, 0, 2, 1, 1, 1, 0, 2, 0, 1, 2, 0, 1, 2, 2, 2, 1, 0, 0, 0, 1, 2, 1, 0, 0, 0, 1, 2, 1, 0, 2, 1, 0, 2, 0, 1, 1, 1, 1, 1, 1, 1, 2, 0, 2, 1, 2, 0, 0, 0, 0, 0, 0, 0, 1, 2, 1, 0, 1, 2, 2, 2, 1, 0, 1, 2, 2, 2, 1, 0, 0, 0, 1, 2, 0, 1, 2

Offset: 1

Author

Philippe Deléham, Jun 04 2004

Keywords

• easy
• nonn

Comments

Partials sums modulo 3 of the sequence : 1, a(1), a(1), a(2), a(2), a(3), a(3), a(4), a(4), a(5), ...

Crossrefs

Cf. A033485.

Programs

Python

from itertools import islice
from collections import deque
def A094451_gen(): # generator of terms
    aqueue, f, b, a = deque([2]), True, 1, 2
    yield from (1, 2)
    while True:
        a = (a+b) % 3
        yield a
        aqueue.append(a)
        if f: b = aqueue.popleft()
        f = not f
A094451_list = list(islice(A094451_gen(),40)) # Chai Wah Wu, Jun 08 2022