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%I #22 Sep 08 2022 08:45:27
%S 0,1,1,1,2,9,70,901,18851,640033,35182964,3130643763,450777518908,
%T 105028031261801,39595117008180069,24152916346958580289,
%U 23838888839331110565174,38070681323495436614002589,98374616701023368879472124802,411304234356297381789636339794573
%N a(n) = Fibonacci(n-1)*a(n-1) - a(n-2), with a(1)=0, a(2)=1.
%H G. C. Greubel, <a href="/A121879/b121879.txt">Table of n, a(n) for n = 1..99</a>
%p with(combinat);
%p a:= proc(n) option remember;
%p if n < 3 then n-1
%p else fibonacci(n-1)*a(n-1) - a(n-2)
%p fi;
%p end proc;
%p seq(a(n), n = 1..30); # _G. C. Greubel_, Oct 08 2019
%t RecurrenceTable[{a[1]==0,a[2]==1,a[n]==Fibonacci[n-1]a[n-1]-a[n-2]}, a[n], {n,25}] (* _Harvey P. Dale_, Aug 14 2011 *)
%t a[n_]:= a[n]= If[n<3, n-1, Fibonacci[n-1]*a[n-1]-a[n-2]]; Table[a[n], {n, 25}] (* _G. C. Greubel_, Oct 08 2019 *)
%o (Python)
%o from sympy import fibonacci, cacheit
%o @cacheit
%o def A121879(n):
%o if n <= 2: return n-1
%o else: return fibonacci(n-1)*A121879(n-1)-A121879(n-2)
%o print([A121879(n) for n in range(1, 25)]) # Oct 14 2009; modified by _G. C. Greubel_, Oct 08 2019
%o (PARI) my(m=25, v=concat([0,1], vector(m-2))); for(n=3, m, v[n] = fibonacci(n-1)*v[n-1] - v[n-2]); v \\ _G. C. Greubel_, Oct 08 2019
%o (Magma) [n lt 3 select n-1 else Fibonacci(n-1)*Self(n-1) - Self(n-2): n in [1..25]]; // _G. C. Greubel_, Oct 08 2019
%o (Sage)
%o @CachedFunction
%o def a(n):
%o if (n<3): return n-1
%o else: return fibonacci(n-1)*a(n-1) - a(n-2)
%o [a(n) for n in (1..25)] # _G. C. Greubel_, Oct 08 2019
%o (GAP) a:=[0,1];; for n in [3..25] do a[n]:=Fibonacci(n-1)*a[n-1]-a[n-2]; od; a; # _G. C. Greubel_, Oct 08 2019
%Y Cf. A000045, A058798.
%K nonn
%O 1,5
%A _Roger L. Bagula_ and _Gary W. Adamson_, Sep 09 2006
%E Definition clarified - The Assoc. Editors of the OEIS, Oct 14 2009
%E More terms added by _G. C. Greubel_, Oct 08 2019
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