# What is the meaning of "seed used at cycle"?

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").

``````\$ curl "http://localhost:8732/chains/main/blocks/head/helpers/baking_rights?delegate=tz3RV1MBbZMR6899Okdjb7Mwj6LkbPSUS1eX1&cycle=205"