Читать книгу The Ultimate Mathematical Challenge: Over 365 puzzles to test your wits and excite your mind - Литагент HarperCollins USD, F. M. L. Thompson - Страница 13

Crossnumber 1

A crossnumber works just like a crossword except that, instead of filling each square with one of the letters from A to Z, you have to fill each square with a single digit from 0 to 9.

ACROSS

1. The square of an odd number (2)

3. 18 DOWN divided by six (3)

6. A number divisible by three (3)

7. A factor of 14 ACROSS (3)

9. An odd number that is one more than a cube (2)

10. One more than a number divisible by nine (2)

12. A number divisible by both six and a square greater than one (3)

14. A multiple of 7 ACROSS (3)

16. The sum of twice 1 ACROSS and 14 (2)

18. Seven less than a square (2)

19. One more than three times 6 ACROSS (3)

21. A Fibonacci number divisible by seven (3)

22. A palindrome that is twice a prime (3)

23. (9 ACROSS × 4) − 13 DOWN (2)

DOWN

2. A palindrome (3)

3. (3 × 9 ACROSS) − (1 ACROSS + 23 ACROSS) (3)

4. The product of two primes (2)

5. One less than a perfect number (2)

8. A cube that is also a power of two (3)

9. A factor of 6111 (3)

11. The sum of the digits of 8 DOWN and 21 ACROSS (2)

12. A number divisible by four (2)

13. A prime that is also a Fibonacci number (3)

15. Three times a prime and six greater than a square (3)

17. One less than a multiple of nine (3)

18. A number divisible by three (3)

19. (12 DOWN × 2) − 5 (2)

20. The sum of the digits of 14 ACROSS is one more than twice the sum of the digits of this number (2)

[SOLUTION]