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%I #14 Nov 23 2020 17:07:44
%S 3,7,3,5,7,3,13,2,3,2,5,2,3,2,31,2,3,2,7,2,3,2,13,2,3,2,5,2,3,2,61,2,
%T 3,2,5,2,3,2,13,2,3,2,5,2,3,2,31,2,3,2,7,2,3,2,13,2,3,2,5,2,3,2,127,2,
%U 3,2,7,2,3,2,13,2,3,2,5,2,3,2,31,2,3,2,7
%N Prime numbers arising in A336817.
%C This sequence contains large runs of consecutive terms that are repeated later on.
%H Rémy Sigrist, <a href="/A337013/b337013.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A336817(n) XOR A336817(n+1) (where XOR denotes the bitwise XOR operator).
%e a(7) = A336817(7) XOR A336817(8) = 7 XOR 10 = 13.
%o (PARI) s=0; v=1; for (n=1, 83, s+=2^v; for (w=1, oo, if (!bittest(s, w) && isprime(p=bitxor(v, w)), print1 (p ", "); v=w; break)))
%Y Cf. A308340, A336817.
%K nonn,base
%O 1,1
%A _Rémy Sigrist_, Nov 21 2020