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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A318971 Primes that divide at least one term of A318970.

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%I A318971 #24 Jun 27 2021 03:40:29
%S A318971 3,29,31821709567,28480625878963
%N A318971 Primes that divide at least one term of A318970.
%C A318971 No other terms below 10^14.
%C A318971 If prime p does not divide any of the first A227944(p) <= log_2(p) terms of A318970, then p does not divide any term of A318970, i.e., p does not belong to this sequence.
%C A318971 (2^260+5)/261 is a term (76-digit prime). Hence, a(5) <= (2^260+5)/261.
%C A318971 Any prime p with A318989(p)=0 belongs to this sequence. However, it is unknown if there is a term p with nonzero A318989(p).
%H A318971 Max Alekseyev, <a href="https://mathoverflow.net/q/251717">Iterations of 2^(n-1)+5: the strong law of small numbers, or something bigger?</a>, MathOverflow, 2016.
%e A318971 a(1)=3 divides A318970(k) for all k >= 1.
%e A318971 a(2)=29 divides A318970(k) for all k >= 3.
%e A318971 a(3)=31821709567 divides A318970(k) for all k >= 8.
%e A318971 a(4)=28480625878963 divides A318970(k) for all k >= 11.
%Y A318971 Cf. A227944, A245594, A318970, A318989.
%K A318971 nonn,more,hard
%O A318971 1,1
%A A318971 _Max Alekseyev_, Sep 06 2018