(02-18-2017 09:22 AM)Ángel Martin Wrote: And here's the MCODE for this exercise. It includes four different functions, as follows:

1. FIB, the "straight' Fibonacci number. Enter n in X, result Fn in X and n in Lastx.

2. sFIB, partial sum of Fibonacci numbers. ("s" is the SIGMA char). Straight addition of all Fibonacci numbers up to n.

3. sIFIB, partial sum of the inverse of Fibonacci numbers, the subject of this thread. For n>=46 this is the PSI constant as Gerson explained. The execution time for n=46 is 2.87 seconds on a normal-speed HP-41.

4. FIBI, the "Fibonacci Inverse" Defined as F'n = 1/F'n-2 + 1/F'n-1. Note that this is not the same as the inverse of Fibonacci, which would simply be 1/Fn

Cheers,

ÁM

Gene: And these will be added to which of your roms ? Any room in Sandmath? :-)