A117655 - OEIS

%I #13 Mar 31 2024 08:48:19

%S 0,1,0,0,0,0,1,3,12,34,54,64,69,71,71,72,72,72,72,72,72,72,72,72,72,

%T 72,72,72,72,72,72,72,72,72,72,72,72,72,72,72,72,72,72,72,72,72,72,72,

%U 72,72,72,72,72,72,72,72,72,72,72,72,72,72,72,72,72,72,72,72,72,72,72,72,72,72,72

%N a(n) = floor(f(n)), where f(n) = (5 - 4.37/(f(n-1) + f(n-2))^(1/3))^3, f(0) = 0, and f(1) = 1.

%H G. C. Greubel, <a href="/A117655/b117655.txt">Table of n, a(n) for n = 0..1000</a>

%F a(n) = floor(f(n)), where f(n) = (5 - 4.37/(f(n-1) + f(n-2))^(1/3))^3, f(0) = 0, and f(1) = 1.

%t f[n_]:= f[n]= If[n<2, n, (5 -4.37/(f[n-1]+f[n-2])^(1/3))^3];

%t a[n_]:= Floor[f[n]];

%t Table[a[n], {n,0,100}]

%o (Magma)

%o f:=[n le 2 select n-1 else (5 - 4.37/(Self(n-1) + Self(n-2))^(1/3))^3 : n in [1..101]];

%o A117655:= func< n | Floor(f[n+1]) >;

%o [A117655(n): n in [0..100]];// _G. C. Greubel_, Mar 30 2024

%o (SageMath)

%o @CachedFunction

%o def f(n): return n if n<2 else (5 - 4.37/(f(n-1)+f(n-2))^(1/3))^3

%o def A117655(n): return floor(f(n))

%o [A117655(n) for n in range(101)] # _G. C. Greubel_, Mar 30 2024

%K nonn,less

%O 0,8

%A _Roger L. Bagula_, Apr 11 2006

%E Edited by _G. C. Greubel_, Mar 30 2024