MathDB
Peculiar Years

Source: 1988 IrMO Paper 1 Problem 9

September 28, 2017
number theory

Problem Statement

The year 19781978 was “peculiar” in that the sum of the numbers formed with the first two digits and the last two digits is equal to the number formed with the middle two digits, i.e., 19+78=9719+78=97. What was the last previous peculiar year, and when will the next one occur?