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%I #6 Jan 18 2019 13:05:32
%S 0,0,0,1,1,1,2,4,7,16,46,166,1014,47066,12348246366,
%T 66716521529543607970475115226
%N a(n) = a(n-1) + a(n-2)*a(n-3) + a(n-4)*a(n-5)^a(n-6)
%C First 6 terms are {0,0,0,1,1,1}; thereafter apply the recurrence. Note that 0^0=1.
%H R. Munafo, <a href="http://mrob.com/pub/math/seq-accelerate.html">Accelerating Sequences</a>
%t nxt[{a_,b_,c_,d_,e_,f_}]:={b,c,d,e,f,f+e*d+c*Max[1,b]^Max[1,a]}; NestList[ nxt,{0,0,0,1,1,1},14][[All,1]] (* _Harvey P. Dale_, Jan 18 2019 *)
%K nonn
%O 0,7
%A _Robert Munafo_, Jan 21 2010