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 A218766 Composite numbers with both 10 and -10 as primitive root. 1
 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The powers of primes from A007349. Intersection of A002808, A167797 and A167806. LINKS Arkadiusz Wesolowski, Table of n, a(n) for n = 1..10000 Eric Weisstein's World of Mathematics, Primitive Root EXAMPLE 12769 = 113^2 belongs to this sequence because 113 is in A007349. 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] CROSSREFS Cf. A007349. Sequence in context: A156572 A157990 A261111 * A188186 A112077 A152934 Adjacent sequences: A218763 A218764 A218765 * A218767 A218768 A218769 KEYWORD nonn AUTHOR Arkadiusz Wesolowski, Nov 05 2012 STATUS approved

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Last modified December 1 05:02 EST 2022. Contains 358454 sequences. (Running on oeis4.)