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%I #15 Oct 19 2018 03:19:45
%S 1,7,7,49,2401,5764801,33232930569601,1104427674243920646305299201,
%T 1219760487635835700138573862562971820755615294131238401
%N a(1) = 1, a(2) = 7, a(n) = product of the previous terms for n >= 3.
%H G. C. Greubel, <a href="/A165425/b165425.txt">Table of n, a(n) for n = 1..13</a>
%F a(1) = 1, a(2) = 7, a(n) = Product_{i=1..n-1} a(i), n >= 3.
%F a(1) = 1, a(2) = 7, a(n) = A000420(2^(n-3)) = 7^(2^(n-3)), n >= 3.
%F a(1) = 1, a(2) = 7, a(3) = 7, a(n) = (a(n-1))^2, n >= 4.
%t a[1]:= 1; a[2]:= 7; a[n_]:= Product[a[j], {j,1,n-1}]; Table[a[n],{n,1, 12}] (* _G. C. Greubel_, Oct 19 2018 *)
%o (PARI) {a(n) = if(n==1, 1, if(n==2, 7, prod(j=1,n-1, a(j))))};
%o for(n=1,10, print1(a(n), ", ")) \\ _G. C. Greubel_, Oct 19 2018
%K nonn
%O 1,2
%A _Jaroslav Krizek_, Sep 17 2009
%E More terms from _Vincenzo Librandi_, Apr 21 2010
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