410.--THE MANDARIN'S "T" PUZZLE.

[Illustration]

Before Mr. Beauchamp Cholmondely Marjoribanks set out on his tour in the

Far East, he prided himself on his knowledge of magic squares, a subject

that he had made his special hobby; but he soon discovered that he had

never really touched more than the fringe of the subject, and that the

wily Chinee could beat him easily. I present a little problem that one

learned mandarin propounded to our traveller, as depicted on the last

page.

The Chinaman, after remarking that the construction of the ordinary

magic square of twenty-five cells is "too velly muchee easy," asked our

countryman so to place the numbers 1 to 25 in the square that every

column, every row, and each of the two diagonals should add up 65, with

only prime numbers on the shaded "T." Of course the prime numbers

available are 1, 2, 3, 5, 7, 11, 13, 17, 19, and 23, so you are at

liberty to select any nine of these that will serve your purpose. Can

you construct this curious little magic square?

Amusements in Mathematics · 第 479 / 970 题