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%I #7 Oct 27 2019 14:29:14
%S 1,2,5,10,13,26,41,65,82,130,137,149,205,229,274,293,298,397,410,458,
%T 509,533,586,661,677,685,709,745,761,794,809,877,881,1018,1066,1145,
%U 1217,1249,1277,1322,1354,1370,1418,1465,1490,1522,1601,1618,1754,1762,1781,1937,1985,2053,2290
%N Numbers k dividing nonzero terms in A003095.
%C k is a term if and only if A328699(k) = 0, in which case all the indices m such that k divides A003095(m) are m = t*A248218(k), t = 0, 1, 2, 3, ...
%e 41 divides A003095(7) = 210066388901, so 41 is in this sequence. In addition, 41 divides A003095(m) if and only if 7 divides m.
%e 29 is not a term: {A003095(n) mod 29} = {0, 1, 2, 5, 26, 10, 14, 23, 8, 7, 21, 7, 21, 7, 21, ...}, so 29 does not divides A003095(m) for any m > 0.
%o (PARI) v(n) = my(v=[0],k,flag=1); for(i=2, n+1, k=(v[#v]^2+1)%n; v=concat(v, k); for(j=1, i-1, if(v[j]==k, flag=0)); if(flag==0, break())); v
%o a(n) = !(v(n)[#v(n)])
%Y Cf. A003095, A328699, A248218.
%Y The primes in this sequence are given by A247981.
%K nonn
%O 1,2
%A _Jianing Song_, Oct 26 2019
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