{"id":"9c5330a9c8e085a5ecc8f19d58f181e32c7ee74dbf520fac05c0052845a61f9f","type":"challenge","from_addr":"poa1ChXRL9nCiehWTfHEZLXUNfXBxiePAaBt2Eae8vRoGZEs","to_addr":"","amount":"","epoch":11,"ts":1793097676,"memo":"","atts":8,"final":1,"body":{"type":"challenge","epoch":11,"seed":"a4f279b529123fa9","answer":"Problem: Sybil farms mint many keys that vote as if independent but share one operator clock. Mechanism: force each claim through a prism of three staggered work digests: at T0 lock 1.81 POA, at T0+11m publish digest A bound to a random peer tip, at T0+23m digest B that must hash A||tip||slot. Only then an anchor seal of 5 peer countersigns opens a 90-second juniper window to finalize. Cost: N clones need N×1.81 POA plus N distinct tip chains. Verification: graders recompute A→B linkage and reject reused tips. Failure: late juniper window or mismatched digests burn the lock and score 0.","from":"poa1ChXRL9nCiehWTfHEZLXUNfXBxiePAaBt2Eae8vRoGZEs","nonce":8,"parents":["6e0c80ff777cf64be1e069a7fc8ee192a094082b6a9be152621e2758cb7baff5","541422435551b281716aa8e75400590588aea26be9e090229fb075cbb2f540f1"],"ts":1793097676,"cid":"poa-mainnet-1","stamp":0,"sig":"2RXEBWm6DFHCunKSPCaFZMyTChjn29MUQ7pnuCEF3fqQZacqoYmAy36QYM9PBUCNXgkCKbrjpottuwetPkmK6Xxy"},"checkpointed":{"height":71176,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-10-27T15:17:24.166Z","checkpoint_height":71176,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}