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A089588 a(n) = A089587(2^n+1) for n >= 0. 1
1, 2, 2, 7, 2, 9, 38, 79, 2, 220, 821, 1780, 2168 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
COMMENTS
A089587(n) is the smallest integer k, 0 < k < n, that most often satisfies the condition: k^m > k^(m+1) (modulo n) as m varies from 1 to n-1, for n > 2, with a(1)=0 and a(2)=1. It is conjectured that A089587(n)=2 only when n is a Fermat number 2^(2^j) + 1 for j >= 0.
LINKS
FORMULA
Conjecture: a(2^k+1) = 2 for k >= 0.
PROG
(PARI) {a(n)=local(A); n>=0; M=0; A=1; for(k=1, 2^n, S=sum(j=1, 2^n, if(k^j%(2^n+1)>k^(j+1)%(2^n+1), 1, 0)); if(S>M, M=S; A=k)); A}
CROSSREFS
Sequence in context: A138115 A021444 A029632 * A325211 A211780 A014840
KEYWORD
nonn,hard,more
AUTHOR
Paul D. Hanna, Nov 09 2003
EXTENSIONS
Definition corrected by Max Alekseyev, Sep 05 2023
STATUS
approved

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Last modified March 19 07:21 EDT 2024. Contains 370955 sequences. (Running on oeis4.)