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A103338 Largest primitive root of numbers in sequence A103336.

%I A103338 #10 Feb 16 2025 08:32:56
%S A103338 0,1,8,14,15,21,27,24,35,33,35,34,45,51,55,56,55,63,69,68,69,77,77,75,
%T A103338 80,77,86,91,92,99,104,110,115,117,115,123,118,128,117,134,135,141,
%U A103338 147,146,152,153,155,159,165,171,175,176,189,188,189,195,207,207,214
%N A103338 Largest primitive root of numbers in sequence A103336.
%H A103338 Robert Israel, <a href="/A103338/b103338.txt">Table of n, a(n) for n = 1..10000</a>
%H A103338 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PrimitiveRoot.html">Primitive Root.</a>
%p A103338 f:= proc(n) local m; uses NumberTheory;
%p A103338   if n::odd then
%p A103338     if NumberOfPrimeFactors(n,distinct) > 1 then return NULL fi;
%p A103338   elif n mod 4 = 0 or NumberOfPrimeFactors(n,distinct) > 2 then return NULL
%p A103338   fi;
%p A103338   m:= PrimitiveRoot(n, ith=Totient(Totient(n)));
%p A103338   if isprime(m) then NULL else m fi
%p A103338 end proc:
%p A103338 f(1):= 0:map(f, [$1..300]); # _Robert Israel_, Dec 01 2024
%Y A103338 Cf. A001918, A046144, A046145, A046146, A103309, A103310, A103335, A103336, A103337.
%K A103338 nonn
%O A103338 1,3
%A A103338 _Harry J. Smith_, Jan 31 2005
%E A103338 Offset changed by _Robert Israel_, Dec 01 2024