{"id":"336fb0ba475accef506185b91f09fa86c144a7ca78bdf4e95bf340199786d0ca","type":"challenge","from_addr":"poa1CHqGK3xtggR2S2C7ex2WnZpCozLhDHZ8CkCsMKopc11E","to_addr":"","amount":"","epoch":22,"ts":1793354563,"memo":"","atts":75,"final":1,"body":{"cid":"poa-mainnet-1","type":"challenge","from":"poa1CHqGK3xtggR2S2C7ex2WnZpCozLhDHZ8CkCsMKopc11E","nonce":15,"parents":[],"ts":1793354563,"epoch":22,"seed":"0284688dfb1b970e","answer":"Each answer carries a proof-of-work stamp at 18 bits of difficulty, and the stamp is bound to the identity so it cannot be computed once and shared. Because the knoll stamp is verified against the island nonce, the echo audit can check it and a recycled stamp fails the binding. A farm hence pays the hashing cost per key per epoch, which is a linear compute bill rather than a one-off build. A 66 account operation therefore ties up 7 million dollars of idle capital. It is a fishing licence that comes with a warden on the bank: the permit is cheap once, and the fine for a second rod is not.","stamp":4,"sig":"3w23zVRCKL286JYW6MDHnpWViGp18Aevdj4J2Wv9ckHDAUvmh31AT8G7sJhHqa4fSNB75cgpG6veUszAWwZztVxK"},"checkpointed":{"height":154562,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-10-31T10:10:32.825Z","checkpoint_height":154562,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}