/**
 * Determine if a given year is a leap year
 * @param {number} year - The year to check
 * @returns {boolean} true if the year is a leap year, false otherwise
 * @example
 * isLeapYear(2000); // Returns true (divisible by 400)
 * isLeapYear(2020); // Returns true (divisible by 4 but not 100)
 * isLeapYear(2100); // Returns false (divisible by 100 but not 400)
 * isLeapYear(2023); // Returns false (not divisible by 4)
 */
export declare const isLeapYear: (year: number) => boolean;