(12C) Find the Nth Harmonic number

[Gamo]

Information about Harmonic Number

https://en.wikipedia.org/wiki/Harmonic_number

Instead of calculating the sum of the reciprocals of the first N natural numbers

n
1 + Σ (1/x) with this summation its easy to do on some calculator that already
x=2

have this Summation Function with this program the computation speed

is fast since it doesn't have to continue sum up all the needed reciprocals from 2 up to N

----------------------------------------------------
Example: Find 50th of the Harmonic Number

50 [R/S] display answer ≈ 4.499

----------------------------------------------------
Program:

Code:


STO 0
1/x
ENTER ENTER ENTER  // press [ENTER] three times
120
1/x
x 
x
12
1/x
-
x
2
1/x
+
x
.5772156649  // this is Euler's Constant
+
RCL 0
LN
+

Gamo

Remark:
The Summation Formular above can be use to test on Casio fx-911ex as shown above.