As a teacher, I feel like I have to warn that type of learning can be counterproductive. The goal is to retain the Kanji. Aiming for 50 a week is a setup for failure. NO ONE (barring strange neural conditions) can retain that much. If you are completely new to the language, start with 5 a week. If you are intermediate, go with 5 a week. If you are advanced, go with 5 a week. Basically, go for about 5 a week. As you move on, you can bump it to 10. But put 5 of those 10 as review Kanji from previous lists.
There's a limit the brain can absorb and recall. It's called cognitive load. 50 is way past it. It's estimated to be between 5 and 8 facts per lesson. Responsibly, aim for 5. For cramming before a test, aim for 8.
I heard 7 was the most numbers a person can remember in a sequence.
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It's between 5 and 8. 7 is often cited. But there are always error bars.