Problem Statement - https://www.hackerrank.com/challenges/python-quest-1 Program to print below output with single for loop and no string operation. n = 5 1 22 333 4444 Code - for i in range(1,int(raw_input())): print int(i- (10*(i/10)))*(((10**i-1))/9) or print i*(10** (i)-1)/9 Resources - http://math.stackexchange.com/questions/1352084/expressing-the-infinite-sum-1-22-333-4444 https://en.wikipedia.org/wiki/Repdigit Note that for integers greater than 0 and less than 10. ( 10 1 / 9 ) X 1 = 1 ( 10 2 / 9 ) X 2 = 22 ( 10 3 / 9 ) X 3 = 333 ( 10 4 / 9 ) X 4 = 4444 ( 10 5 / 9 ) X 5 = 55555 ( 10 6 / 9 ) X 6 = 666666 ( 10 7 / 9 ) X 7 = 7777777 ( 10 8 / 9 ) X 8 = 88888888 ( 10 9 / 9 ) X 9 = 999999999
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