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%I #14 Jun 23 2020 18:52:42
%S 4,3,4,2,4,8,16,64,512,16384,2097152,2147483648,140737488355328,
%T 1180591620717411303424,40564819207303340847894502572032,
%U 365375409332725729550921208179070754913983135744
%N Smallest difference>1 between d and p/d for any divisor d of the partial product p of the sequence, starting with 4.
%C a(n) is a power of two for n>1 and log_2(a(n))=A073941(n) for n>2. - _Ralf Stephan_, Apr 16 20.
%H R. Stephan, <a href="http://arXiv.org/abs/math.CO/0305348">[math/0305348] On a sequence related to the Josephus problem</a>
%H <a href="/index/J#Josephus">Index entries for sequences related to the Josephus Problem</a>
%o (PARI) p=4; print1(p, ", "); for(n=1, 50, v=divisors(p); r=sqrt(p); t=0; for(k=1, matsize(v)[2], if(v[k]>=r, t=k; break)); if(v[t]^2==p, u=t, u=t-1); if(v[t]-v[u]<2, u=u-1; t=t+1); print1(v[t]-v[u]", "); p=p*(v[t]-v[u]))
%Y Cf. A082120, A003681 (starts with 2, 3), A082126.
%Y Cf. A029744.
%K nonn,hard
%O 0,1
%A _Ralf Stephan_, Apr 04 2003
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