Maths Crossword

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Across
  1. 4. Pi, e, 0.11010010001…etc.
  2. 6. Who wrote Elements?
  3. 8. Zeno loved these
  4. 9. x=((-b)+-sqrt((b^2)-4ac))/2a
  5. 13. Do triangle angles always add up to 180 degrees?
  6. 14. His sieve for prime numbers?
  7. 17. “Reason is immortal, all else is mortal.”
  8. 18. Not on the number line, but plane
  9. 19. (1+(sqrt5))/2
  10. 20. How many rabbits?
  11. 21. Soroban, when in a competition called anzan (all in Japanese)
  12. 22. Biggest number actually used
Down
  1. 1. Ooh, you got 7, 8, 9 and 9 in which game?
  2. 2. All go in the focus.
  3. 3. _________numbers, e.g.220 and 284
  4. 5. EUREKA!
  5. 7. One of them is the cube
  6. 10. God Heh, in hieroglyphs?
  7. 11. Angles of triangles
  8. 12. I made this when I was… (write in letters)
  9. 15. Mr Hardy with Mr Ramanujan
  10. 16. Feminist symbol?
  11. 21. Infinity…ies?
  12. 23. 1+(1/4)+(1/9)+(1/16)…=