%I #15 Sep 09 2020 02:07:17
%S 1,2,41,109,151,229,251,271,313,337,362,367,409,439,542,626,674,733,
%T 761,818,878,971,991,1021,1031,1069,1289,1297,1303,1429,1471,1489,
%U 1681,1759,1783,1789,1811,1871,1873,1879,2062,2137,2342,2411,2441,2551,2594
%N Numbers whose smallest primitive root (A046145) is not prime.
%H Robert Israel, <a href="/A103335/b103335.txt">Table of n, a(n) for n = 1..10000</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PrimitiveRoot.html">Primitive Root.</a>
%p filter:= proc(n)
%p local r;
%p r:= numtheory:-primroot(n);
%p r <> FAIL and not isprime(r)
%p end proc:
%p filter(1):= true:
%p select(filter, [$1..3000]); _Robert Israel_, Sep 08 2020
%t L = {}; Do[ If[!PrimeQ[ Min[ Select[ Range[n], CoprimeQ[#, n] && MultiplicativeOrder[#, n] == CarmichaelLambda[n] &]]],
%t L = Append[L, n]], {n, 1, 3000}]; L (* _Jonathan Sondow_, May 17 2017 *)
%Y Cf. A001918, A046144, A046145, A046146, A103309, A103310, A103336, A103337, A103338.
%K nonn
%O 1,2
%A _Harry J. Smith_, Jan 31 2005
%E Offset changed by _Robert Israel_, Sep 08 2020
|