Drenom
Joined: Oct 17, 2018
• Posts: 4
October 17th, 2018 at 3:19:06 PM permalink
Hi, I am trying to calculate probability of winning anything on at least one payline.
3 rows x 5 columns, 20 paylines.
All pay lines have length 5.
7 symbols, 7th is wild
no scatter
The way I tried it is under the spoiler.
Any help is appreciated.

Tried to calculate it as P(777) = p(777)*20 - ( p(777)^2+175*2/20/19*(p(777)-p(777)^2 )/ Lenght(777) ) * 190 + ( p(777)^3 + 294*2/20/19/18*(p(777)-p(777)^3)/ Lenght(777) ) *1140/2 -....+
175 - Sum of shared stops between all 20 paylines in combinations of two
190 - C(2, 20)
294 - Sum of shared stops between all 20 paylines in combinations of three
p(i) - probability of i-th winning event (777 - n71*n72*n73*(N4-n74)*N5 / (N1*N2*N3*N4*N5) )
Length(i) - length of i-th combination (777 - L = 3, 7777 - L = 4)
The shortest winnig combination has l = 3
I tried approximating till combination of shared stops between 7 paylines
I calculated this for all combinations, took a sum, but it wasn't even remotely close to simulation
Difference was more than 2 times.
ThatDonGuy
Joined: Jun 22, 2011
• Posts: 4744
October 17th, 2018 at 4:24:42 PM permalink
Not nearly enough information.

I have a feeling the shape of the lines is important, as you have to count how many sets of results have more than one winning payline.
Also, what do you need for a win - 2? 3? 5? Does it depend on the symbol? (I assume lines have to start from the left reel.)

Are there just seven symbols per reel? Do they come up with equal probability?
CrystalMath
Joined: May 10, 2011
• Posts: 1892
October 17th, 2018 at 8:14:53 PM permalink
It matters how much the lines overlap and the minimum symbols for each win. Is there a wild symbol? Which reels have wilds? This is easiest done through simulation.
I heart Crystal Math.
Drenom
Joined: Oct 17, 2018