A218766 Composite numbers with both 10 and -10 as primitive root.

289, 841, 3721, 4913, 9409, 11881, 12769, 22201, 24389, 32761, 37249, 52441, 54289, 66049, 72361, 83521, 97969, 113569, 151321, 187489, 212521, 226981, 259081, 292681, 332929, 351649, 491401, 502681, 674041, 707281, 734449, 877969, 885481, 908209, 912673

Offset: 1

Author

Arkadiusz Wesolowski, Nov 05 2012

Keywords

• nonn

Comments

The powers of primes from A007349.

Intersection of A002808, A167797 and A167806.

Examples

			12769 = 113^2 belongs to this sequence because 113 is in A007349.
		

Links

• Arkadiusz Wesolowski, Table of n, a(n) for n = 1..10000
• Eric Weisstein's World of Mathematics, Primitive Root

Crossrefs

Cf. A007349.

Programs

Mathematica

lst = {}; r = 912673; Do[If[PrimeQ[i] && MultiplicativeOrder[10, i] == MultiplicativeOrder[-10, i] == i - 1, n = 2; While[(p = i^n) <= r, AppendTo[lst, p]; n++]], {i, Floor@Sqrt[r]}]; Sort[lst]