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

%I A381508 #40 Apr 26 2025 10:25:06
%S A381508 1,7,728,14,208,728,342,28,2184,1456,354312,728,9520,2394,1456,56,
%T A381508 709928,2184,5227320,1456,124488,354312,279840,728,1040,9520,6552,
%U A381508 2394,243880,1456,71040,112,4606056,4969496,35568,2184,20362908,5227320,123760,1456,201840
%N A381508 Pisano period of Hexanacci numbers (A001592) mod n.
%H A381508 Chai Wah Wu, <a href="/A381508/b381508.txt">Table of n, a(n) for n = 1..222</a>
%H A381508 Martin Guerra and Doron Zeilberger, <a href="http://sites.math.rutgers.edu/~zeilberg/tokhniot/PisanoP.txt">Maple program</a>
%p A381508 # load programs from linked file:
%p A381508 seq(Pis([[0$5, 1],[1$6]],n,400000), n=1..16);
%o A381508 (Python)
%o A381508 from math import lcm
%o A381508 from functools import lru_cache
%o A381508 from sympy import factorint
%o A381508 @lru_cache(maxsize=None)
%o A381508 def A381508(n):
%o A381508     if n == 1:
%o A381508         return 1
%o A381508     f = factorint(n).items()
%o A381508     if len(f) > 1:
%o A381508         return lcm(*(A381508(a**b) for a,b in f))
%o A381508     else:
%o A381508         k, x = 1, (0,0,0,0,1,1)
%o A381508         while x != (0,0,0,0,0,1):
%o A381508             k += 1
%o A381508             x = x[1:]+(sum(x) % n,)
%o A381508         return k # _Chai Wah Wu_, Apr 25 2025
%Y A381508 Cf. A001175, A001592.
%K A381508 nonn
%O A381508 1,2
%A A381508 _Martin Guerra_ and _Doron Zeilberger_, Apr 24 2025
%E A381508 a(17)-a(41) from _Alois P. Heinz_, Apr 25 2025