OFFSET
1,1
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
Arto Lepistö, Francesco Pappalardi and Kalle Saari, Transposition Invariant Words, Theoret. Comput. Sci., Vol. 380, No. 3 (2007), pp. 377-387.
EXAMPLE
The primitive roots modulo 97 are 5, 7, 10, 13, 14, 15, 17, 21, 23, 26, 29, 37, 38, 39, ..., and 7 divides 98, so 97 is a member of this sequence.
PROG
(PARI) forprime(p=2, 1000, i=0; fordiv(p+1, X, if(znorder(Mod(X, p))==eulerphi(p), i=1)); if(i==1, print1(p", "))) \\ V. Raman, May 04 2013
(Magma) [p: p in PrimesUpTo(700) | exists{r: r in [1..p-1] | IsPrimitive(r, p) and IsZero((p+1) mod r)}]; // Bruno Berselli, May 10 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, May 04 2013
EXTENSIONS
More terms from V. Raman, May 04 2013
STATUS
approved