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%I #15 Jan 28 2016 05:39:33
%S 2,2,4,16,4294967296
%N a(1) = a(2) = 2; for n>2, a(n) = a(n-2)^a(n-1).
%C The next term is too large to include.
%H <a href="/index/Di#divseq">Index to divisibility sequences</a>
%t a=2; b=2; lst={a,b}; Do[c=a^b; AppendTo[lst,c]; a=b; b=c, {n,3}]; lst (* _Vladimir Joseph Stephan Orlovsky_, Dec 28 2010 *)
%K nonn
%O 1,1
%A Emre Aladag (emrealadag(AT)ttnet.net.tr), Jan 26 2003
%E Corrected by _Brian Galebach_, Dec 03 2003