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 19

Crossnumber 2

ACROSS

1. The highest common factor of 5 DOWN and 8 DOWN (2)

3. A prime factor of 2007 (3)

5. 3 DOWN plus the square root of 4 DOWN (3)

6. The product of three consecutive integers, two of which are prime (3)

7. One less than a multiple of 2 DOWN (3)

9. Five less than 14 ACROSS (4)

11. Seven more than the product of the digits of 22 ACROSS (2)

13. Three more than a triangular number (2)

14. 9 ACROSS plus five (4)

16. A square whose digit sum is three more than its square root (3)

18. Three times the product of two consecutive prime numbers (3)

21. The mean of 11 ACROSS and 21 ACROSS is 16 ACROSS (3)

22. Twice a prime number (3)

23. Two less than a square (2)

DOWN

1. Eight less than a multiple of nine (3)

2. A prime factor of 12 DOWN (2)

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

4. A square (2)

5. One less than twice a triangular number (3)

7. 10 DOWN minus three (4)

8. One third the product of three consecutive numbers, two of which are prime (3)

10. 7 DOWN plus three (4)

12. A number whose digit sum is equal to one of its factors (3)

15. The product of two consecutive prime numbers (3)

17. p⁴ + 1, where p is prime (3)

19. The sum of 16 ACROSS and 3 ACROSS (3)

20. Six less than twice 13 ACROSS (2)

21. Fifteen plus the mean of 1 ACROSS and 11 ACROSS (2)

[SOLUTION]