A Korean living in Vietnam has won the country's largest-ever lottery prize claimed by a foreigner, taking home a jackpot worth about 102.8 billion Vietnamese dong, or approximately 5.8 billion won (about $4.2 million), according to local officials. Vietnamese media outlet VN Express reported Tuesday that state-run lottery operator Vietlott awarded the winner, identified only as Mr. A, the top prize in its Power 6/55 lottery. The odds of matching all six winning numbers were approximately one in 28.9 million. Mr. A, who lives in Hanoi and works for a foreign-invested company, said he had been buying 20 to 30 tickets twice a week for the past four to five years. When jackpots grew particularly large, he sometimes purchased as many as 50 tickets for a single drawing. The winning ticket was selected using numbers he chose himself. The win marks the fourth time a foreign national has claimed a Vietlott jackpot. Previous winners included two Koreans and one Chinese citizen, but Mr. A's prize is the largest ever won by a foreigner in Vietnam. The previous record belonged to another Korean, who