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%I #7 Mar 10 2021 01:19:14
%S 10,17,18,20,30,34,36,40,49,50,51,54,55,60,68,70,72,73,80,85,90,98,99,
%T 100,102,108,110,115,118,119,120,126,136,140,144,145,146,147,150,153,
%U 160,165,170,180,187,190,194,196,198,199,200,204,207,210,211,216,219,220,230,236,238,240,245,250
%N Moduli n for which A248218(n) = 6.
%C If x is a member of this sequence, and y is a member of this sequence or A248219 or A256342 or A256343, then LCM(x,y) is a member of this sequence. - _Robert Israel_, Mar 09 2021
%H Robert Israel, <a href="/A256346/b256346.txt">Table of n, a(n) for n = 1..10000</a>
%p filter:= proc(n) local x, k, R,p;
%p x:= 0; R[0]:= 0;
%p for k from 1 do
%p x:= x^2+1 mod n;
%p if assigned(R[x]) then return evalb(k-R[x] = 6)
%p else R[x]:= k
%p fi
%p od;
%p end proc:
%p select(filter, [$1..1000]); # _Robert Israel_, Mar 09 2021
%o (PARI) for(i=1,250,A248218(i)==6&&print1(i","))
%Y Cf. A248218, A248219, A256342 - A256349, A003095, A247981.
%K nonn
%O 1,1
%A _M. F. Hasler_, Mar 25 2015