Consider three positive integers x, y and z in geometric sequence with x < y < z < 2011 and, x+y=z+1 and determine all possible triplets (x,y,z) that satisfy the given conditions.

DEFDBL A-Z
FOR x = 1 TO 2011
 FOR y = x + 1 TO 2011
   z = x + y - 1
   IF z < 2011 THEN
      IF x * z = y * y THEN PRINT x; y; z
   END IF
 NEXT
NEXT x

 4  6  9
 25  40  64
 169  273  441

Posted by Charlie on 2011-08-03 18:30:22