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A123365 Values of n such that A046530(n) = (n+2)/3, where A046530 is the number of distinct residues of cubes mod n. 2
1, 7, 13, 19, 31, 37, 43, 61, 67, 73, 79, 97, 103, 109, 127, 139, 151, 157, 163, 181, 193, 199, 211, 223, 229, 241, 271, 277, 283, 307, 313, 331, 337, 349, 367, 373, 379, 397, 409, 421, 433, 439, 457, 463, 487, 499, 523, 541, 547, 571, 577, 601, 607, 613, 619 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Conjecture. With the exception of the first term a(1)=1, this is exactly the sequence of primes of the form 6k+1 (A002476). This has been verified up to a(n)=2000.

LINKS

R. J. Mathar, Table of n, a(n) for n = 1..10000

MAPLE

n := 1 :

a := 1 :

while n <= 10000 do

    printf("%d %d\n", n, a) ;

    a := a+1 ;

    while A046530(a) <> (a+2)/3 do

        a := a+1 ;

    end do:

    n := n+1 ;

end do: # creates b-file R. J. Mathar, Sep 21 2017

CROSSREFS

Cf. A002476, A046530, A123722, A123723.

Sequence in context: A129389 A107925 A002476 * A144921 A272409 A272406

Adjacent sequences:  A123362 A123363 A123364 * A123366 A123367 A123368

KEYWORD

nonn

AUTHOR

John W. Layman, Oct 12 2006

STATUS

approved

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Last modified March 22 01:06 EDT 2019. Contains 321406 sequences. (Running on oeis4.)