A381508 Pisano period of Hexanacci numbers (A001592) mod n.

1, 7, 728, 14, 208, 728, 342, 28, 2184, 1456, 354312, 728, 9520, 2394, 1456, 56, 709928, 2184, 5227320, 1456, 124488, 354312, 279840, 728, 1040, 9520, 6552, 2394, 243880, 1456, 71040, 112, 4606056, 4969496, 35568, 2184, 20362908, 5227320, 123760, 1456, 201840

Offset

1,2

Links

Chai Wah Wu, Table of n, a(n) for n = 1..222

Martin Guerra and Doron Zeilberger, Maple program

Maple

# load programs from linked file:
seq(Pis([[0$5, 1], [1$6]], n, 400000), n=1..16);

Prog

(Python)
from math import lcm
from functools import lru_cache
from sympy import factorint
@lru_cache(maxsize=None)
def A381508(n):
    if n == 1:
        return 1
    f = factorint(n).items()
    if len(f) > 1:
        return lcm(*(A381508(a**b) for a, b in f))
    else:
        k, x = 1, (0, 0, 0, 0, 1, 1)
        while x != (0, 0, 0, 0, 0, 1):
            k += 1
            x = x[1:]+(sum(x) % n, )
        return k # Chai Wah Wu, Apr 25 2025

Crossrefs

Cf. A001175, A001592.

Sequence in context: A222727 A201485 A083978 * A162138 A067448 A249897

Adjacent sequences: A381505 A381506 A381507 * A381509 A381510 A381511

Keyword

nonn

Author

Martin Guerra and Doron Zeilberger, Apr 24 2025

Extensions

a(17)-a(41) from Alois P. Heinz, Apr 25 2025

Status

approved