Mathematician’s Crossword 1

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13

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10

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22

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25

ACROSS: 1. The smallest number that can be represented as the sum of two cubes in two different ways. 4. A perfect number. 6. The cube of twice the difference of two perfect numbers. 8. Twice a perfect number. 10. Sum of the same power of three odd numbers; also, multiple of 7 down. 11. Multiple of 14 down; also, the reverse of a square. 13. Its square is the sum of the square and the cube of 19 down. 16. A prime which is the sum of three consecutive primes. 18. A lucky-unlucky product. 20. A Fibonacci number times two; also, twice the sum of two perfect numbers. 21. Orwell year. 22. Square of a perfect number times the cube of a palindromic prime; also, a factor of 12 down. 25. Product of two primes: any shuffle of its digits is a prime; also. a factor of 3 down. 26. Product of a one-digit. a two-digit and a three-digit low prime; also. sum of the two primes of 16 down.

(Clipped from Mensa newsletter before 2001)

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5

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26

DOWN: 1. Fourth power of a teen number augmented by 25 across. 2. A perfect number. 3. Its digits are: square, prime, prime, perfect. It is an even multiple of 25 across. It is smaller by a perfect number than the square of a number of two consecutive digits; the product of these two digits is the even factor mentioned above. 4. The double area of a triangle whose sides are even, consecutive Pythagorean numbers. 5. Sum of two powers; the base of each is the power of the other. The ratio of the bases is 2. 7. A square minus one; also. non-prime factor of 10 across. 9. A prime of consecutive digits. 12. Cube of an isodigital number; also, 22 across times a perfect number. 14. Unlucky prime. 15. Prime repeated factor of 22 across. 16. Tchaikovsky opus; also, the difference of the primes of 26 across. 17. Even multiple of 15 down; also a Fibonacci sum. 19. A square minus one; also. the building block of 13 across. 20. A "cancerous" number. 23. Sum of its reverse and a square (see 24 down). 24. Sum of its reverse and the square in 23 down Mathemetician'sCrossword.doc