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A073023 Number of solutions to the equation n^x==1 (modx) 1<=x<=n. 0
1, 1, 2, 2, 3, 2, 5, 2, 4, 3, 7, 2, 8, 2, 6, 5, 7, 2, 11, 2, 8, 5, 11, 2, 12, 3, 9, 4, 14, 2, 18, 2, 7, 6, 12, 5, 16, 2, 10, 6, 19, 2, 22, 2, 9, 9, 16, 2, 19, 3, 13, 6, 18, 2, 20, 5, 14, 7, 21, 2, 28, 2, 10, 9, 17, 5, 29, 2, 17, 6, 31, 2, 23, 2, 10, 9, 23, 5, 32, 2, 16, 5, 26, 2, 28, 6, 14, 9 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..88.

FORMULA

Conjecture: for n>100, sum(k=1, n, a(k)) > n^(3/2)

PROG

(PARI) a(n)=sum(i=1, n, if((n^i-1)%i, 0, 1))

CROSSREFS

Sequence in context: A285573 A325339 A010846 * A173754 A180125 A272209

Adjacent sequences:  A073020 A073021 A073022 * A073024 A073025 A073026

KEYWORD

easy,nonn

AUTHOR

Benoit Cloitre, Aug 21 2002

STATUS

approved

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Last modified August 3 05:32 EDT 2020. Contains 336197 sequences. (Running on oeis4.)