From the trend: Brazil's Vasco stun Boca at home in the cup semifinal
Who reaches the final after Tuesday's match: Boca or Vasco?
Forecast before the AIs
Your forecast first — then we show what 9 AIs forecast.
Who reaches the final after Tuesday's match: Boca or Vasco?
We’ll know the answer
Boca — 1 AIYou are here
🇨🇳Z.ai
Z.ai: Vasco has a one-goal lead and can advance with just a draw
Vasco — 8 AIsYou are here
🇺🇸ChatGPT🇺🇸Claude🇺🇸Gemini🇨🇳Kimi🇺🇸Grok🇺🇸Meta AI🇨🇳DeepSeek🇨🇳Wenxin
ChatGPT: Vasco already leads, and even a draw in the return match sends it through.
We check it on: conmebol.com
We’ll know the answer
Download Poly A1 for free — see your forecasting skill every day
How often your forecasts come true, whether you beat the AIs, and how you improve by month, quarter and year.
How we will check the answer
We check it on: conmebol.com
The answer is due on Oct 21, 2026.
When the day comes, an AI judge that searches the web checks the answer. If the result is disputed, another judge checks it again — both checks stay on this page.
Exact wording, as the AIs got it (in English)
Which team will reach the 2026 Copa Sudamericana final from the Boca Juniors vs Vasco da Gama semifinal, after the second leg in Rio de Janeiro on Tuesday, October 20, 2026 (including any penalty shootout), as shown on conmebol.com by 2026-10-21T03:30Z: Boca Juniors or Vasco da Gama?
Fingerprint matches ✓
The question and the AIs’ chances are exactly as they were when we sealed them.
Sealed by us on . Sent to OpenTimestamps, a free public registry that does not belong to us, 6 days before the answer was due. Waiting to be fixed for good.
A fingerprint is a short code taken from a record when it is written. Change even one letter and the code is different.
The fingerprint itself, line 39 of the book: cf53c0d5440a6d3ef83cc0792f3987818ef96c648cae8b0d86f34bebd2127a2c
Check it yourself, without us
- The book of questions: duels.jsonl
- The list we sent and the registry’s answer: polya1-trends-2026-10-14-232708Z.txt · polya1-trends-2026-10-14-232708Z.txt.ots
- The first 39 lines of the book give the same number as the list:
head -n 39 duels.jsonl | shasum -a 256
- The registry’s answer shows when the list existed:
ots verify polya1-trends-2026-10-14-232708Z.txt.ots
or drop both files on opentimestamps.org.