Diophantus' Riddle

``Diophantus' youth lasts 1/6 of his life. He grew a beard after 1/12 more of his life. After 1/7 more of his life,Diophantus married. Five years later, he had a son. The son lived exactly half as long as his father, and Diophantus diedjust four years after his son's death. All of this totals the years Diophantus lived.''

Let be the number of years Diophantus lived, and let be the number of years his son lived. Then the above word problemgives the two equations

References

Pappas, T. ``Diophantus' Riddle.'' The Joy of Mathematics. San Carlos, CA: Wide World Publ./Tetra, pp. 123 and 232, 1989.

• Heine-Borel Theorem
• Heine Hypergeometric Series
• Heisenberg Group
• Heisenberg Space
• Held Group
• Helen of Geometers
• Helicoid
• Helix
• Helly Number
• Helly's Theorem
• Helmholtz Differential Equation
• Helmholtz Differential Equation--Bipolar Coordinates
• Helmholtz Differential Equation--Cartesian Coordinates
• Helmholtz Differential Equation--Circular Cylindrical Coordinates
• Helmholtz Differential Equation--Confocal Ellipsoidal Coordinates
• Helmholtz Differential Equation--Confocal Paraboloidal Coordinates
• Helmholtz Differential Equation--Conical Coordinates
• Helmholtz Differential Equation--Elliptic Cylindrical Coordinates
• Helmholtz Differential Equation--Oblate Spheroidal Coordinates
• Helmholtz Differential Equation--Parabolic Coordinates
• Helmholtz Differential Equation--Parabolic Cylindrical Coordinates
• Helmholtz Differential Equation Polar Coordinates
• Helmholtz Differential Equation--Prolate Spheroidal Coordinates
• Helmholtz Differential Equation--Spherical Coordinates
• Helmholtz Differential Equation--Spherical Surface