Pick a number game advice

I have an app in development - it's a pick a number game between 1 & 1,000,000... One number is the jackpot, the other 999,999 numbers are not.

I have 15 different items that will be found on the other numbers (in place of higher or lower), each taking the player through a series of 5 screens.

I want item 1 to be spread randomly across 150,000 numbers, item 2 to be spread randomly across 20,000 numbers and so forth (all items totalling 999,999). I also want the ability to adjust those numbers on the fly through the admin panel.

My developers are saying that to do this they would need to code 1,000,000 entries - which is not practical and would cause everything to crash...

I'm not a coder. Starting to wish I was... But the way I see it is the player either picks the winning number or they don't. If they don't, can't code just randomly choose one of the 15 sequences to take the player through? Showing item one for example no more than 150,000 times? (Or whatever I set it at in the admin panel)

How would you do this? Any advice will be greatly appreciated!

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