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From the Tezos documentation, I understand that the seed derived at the end of cycle n-1 is used to compute the baking rights for cycle n+5 (so 6 cycles difference).
This means that some pictures from this blog post are wrong? See for instance the picture "seed snapshot baking and rewards". There, if I understand it correctly, the seed derived at the cycle n-6 is used to compute the baking rights for cycle n+5 (so 11 cycles difference).
What is the meaning of “seed used at cycle”?
Before we go any further, let's explain what this seed is. For cycle n's baking rights, cycle n - 7 is the cycle where we determine how many rolls each baker has. In order for the chain to determine the number of rolls each baker has, snapshots are taken throughout cycle n - 7, specifically every 256 blocks or 16 snapshots per cycle. A snapshot just has information about how many rolls each baker have. In another words, if a baker change the number of rolls he owns(or people who delegates to him change) in cycle n - 7, it may or may not get reflected for baking rights in cycle n depending on which snapshot is chosen by the chain.
How does the chain determine which of the 16 snapshot is used? This is the through random seed and random_seed is determined by all the relevation nonce revealed by the bakers in cycle n - 6. relevation nonce is a requirement for certain block bakers to reveal to help the chain in creating randomness or random seed. Hence this is why baking rights for cycle n are fully determined in n - 5 because random seed is fully determined (from the relevation nonces).
the seed derived at the cycle n-6 is used to compute the baking rights for cycle n+5 (so 11 cycles difference).
This is incorrect. There is little correlation between cycle n - 6 and n + 5. As explained above, cycle n - 5 is when the baking rights are fully known for cycle n. Cycle n + 5 is usually associated to when the rewards are unfrozen for baking/endorsing during cycle n.
It would appear as though those images are indeed wrong. Hard to determine 100% as there is so much going on with that post. (Side note: "tezzie" is wrong; the correct term is "tez").
Simply ask the chain to find the correct answer:
$ curl "http://localhost:8732/chains/main/blocks/head/helpers/baking_rights?delegate=tz3RV1MBbZMR6899Okdjb7Mwj6LkbPSUS1eX1&cycle=205"
[{"kind":"permanent","id":"proto.005-PsBabyM1.seed.unknown_seed","oldest":194,"requested":205,"latest":204}
The current cycle is 199. The most up to date baking rights have only been assigned out to cycle 204. That's 5 cycles in advance.
