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A332966
a(n) is the largest value in the sequence s defined by s(1) = 0 and for any k > 0, s(k+1) = (s(k)^2+1) mod n.
2
0, 1, 2, 2, 2, 5, 5, 5, 8, 7, 6, 5, 5, 12, 11, 10, 16, 17, 12, 17, 5, 17, 13, 5, 5, 5, 26, 26, 26, 26, 26, 26, 26, 33, 26, 29, 26, 31, 26, 37, 32, 26, 36, 26, 26, 33, 43, 26, 47, 30, 50, 26, 41, 53, 50, 26, 50, 50, 30, 50, 53, 57, 47, 37, 57, 26, 56, 65, 59
OFFSET
1,3
COMMENTS
For any n > 0, the sequence s is eventually periodic, so this sequence is well defined.
a(n) tends to infinity as n tends to infinity.
FORMULA
a(n) >= A003095(k) for any k >=0 and n > A003095(k).
EXAMPLE
For n = 42:
- we have:
k s(k)
- ----
1 1
2 2
3 5
4 26
5 5
6 26
...
- the sequence s has largest value 26, so a(42) = 26.
PROG
(PARI) a(n) = { my (s=0, v=s, w=0); while (!bittest(w, s), w+=2^s; v=max(v, s); s=(s^2+1)%n); v }
CROSSREFS
KEYWORD
nonn
AUTHOR
Rémy Sigrist, Mar 04 2020
STATUS
approved