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Partial products of A004001.
3

%I #11 Apr 27 2021 05:41:33

%S 1,1,1,2,4,12,48,192,768,3840,23040,161280,1128960,9031680,72253440,

%T 578027520,4624220160,41617981440,416179814400,4577977958400,

%U 54935735500800,659228826009600,8569974738124800,119979646333747200,1679715048672460800,25195725730086912000,377935885951303680000

%N Partial products of A004001.

%H G. C. Greubel, <a href="/A172452/b172452.txt">Table of n, a(n) for n = 0..250</a>

%t f[n_]:= f[n]= If[n<3, Fibonacci[n], f[f[n-1]] + f[n-f[n-1]]]; (* f = A004001 *)

%t a[n_]:= Product[f[j], {j,n}];

%t Table[a[n], {n,0,35}] (* modified by _G. C. Greubel_, Apr 27 2021 *)

%o (Sage)

%o @CachedFunction

%o def b(n): return fibonacci(n) if (n<3) else b(b(n-1)) + b(n-b(n-1)) # b=A004001

%o def a(n): return product(b(j) for j in (1..n))

%o [a(n) for n in (0..35)] # _G. C. Greubel_, Apr 27 2021

%K nonn

%O 0,4

%A _Roger L. Bagula_, Feb 03 2010

%E Definition simplified - The Assoc. Editors of the OEIS, Feb 24 2010

%E More terms added by _G. C. Greubel_, Apr 27 2021