OFFSET
1,2
COMMENTS
This sequence is multiplicative. - Leon P Smith, Apr 16 2005
LINKS
T. D. Noe, Table of n, a(n) for n = 1..1000
S. Li, On the number of elements with maximal order in the multiplicative group modulo n, Acta Arithm. 86 (2) (1998) 113, see proof of theorem 2.1
FORMULA
Conjecture: a(5^e) = 1+floor[(5-1)*5^(e+3)/(5^5-1)] if e == {0,2,3,4} (mod 5). a(5^e) = 5+floor[(5-1)*5^(e+3)/(5^5-1)] if e==1 (mod 5). - R. J. Mathar, Oct 22 2017
Conjecture: a(p^e) = 1+floor[(p-1)*p^(e+4)/{gcd(p-1,5)*(p^5-1)}] for primes p<>5 - R. J. Mathar, Oct 22 2017
MAPLE
A052274 := proc(m)
{seq( modp(b^5, m), b=0..m-1) };
nops(%) ;
end proc:
seq(A052274(m), m=1..100) ; # R. J. Mathar, Sep 22 2017
MATHEMATICA
With[{nn=100}, Table[Length[Union[PowerMod[Range[nn], 5, n]]], {n, nn}]] (* Harvey P. Dale, Mar 19 2016 *)
PROG
(PARI) a(n)=my(f=factor(n)); prod(i=1, #f[, 1], my(k=f[i, 1]^f[i, 2]); #vecsort(vector(k, i, i^5%k), , 8)) \\ Charles R Greathouse IV, Sep 05 2013
CROSSREFS
KEYWORD
nonn,mult
AUTHOR
N. J. A. Sloane, Feb 05 2000
STATUS
approved