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A333974
Eventual period of A007660 modulo n.
1
1, 3, 4, 3, 7, 12, 5, 3, 8, 21, 6, 12, 15, 15, 28, 3, 31, 24, 23, 21, 20, 6, 13, 12, 28, 15, 24, 15, 46, 84, 7, 3, 12, 93, 35, 24, 20, 69, 60, 21, 25, 60, 44, 6, 56, 39, 14, 12, 30, 84, 124, 15, 84, 24, 42, 15, 92, 138, 11, 84, 117, 21, 40, 3, 105, 12, 121, 93
OFFSET
1,2
COMMENTS
Multiplicative: If n = p^x * q^y * ... for distinct primes p,q,... then a(n) = a(p^x) * a(q^y) * ...
LINKS
FORMULA
a(n) | a(k*n), k=2,3,...
EXAMPLE
a(1) is trivially 1.
For n=2 the sequence is 0, {0,1,1}, {0,1,1}, hence a(2) = 3.
For n=3 the sequence is 0, {0,1,1,2}, {0,1,1,2}, hence a(3) = 4.
For n=4 the sequence is 0,0,1,1, {2,3,3}, {2,3,3}, hence a(4) = 3.
For n=5 the sequence is 0, {0,1,1,2,3,2,2}, {0,1,1,2,3,2,2}, hence a(5) = 7.
PROG
(PARI) See Corneth link \\ David A. Corneth, Sep 04 2020
CROSSREFS
Sequence in context: A127737 A358125 A299416 * A163108 A350771 A077005
KEYWORD
nonn,mult
AUTHOR
Isaac Kaufmann, Sep 03 2020
EXTENSIONS
More terms from Jinyuan Wang, Sep 04 2020
STATUS
approved