Given, the sum of digits =10n+1 ∴‌‌ Number =10n+1 When, n=0 ∴‌‌ Number =100+1=1+1=2 When, n=1∴ Number =101+1=10+1=11( Sum is 2) When, n=2∴ Number =102+1=100+1=101( Sum is 2) When, n=3∴ Number =103+1=1000+1=1001( Sum is 2) Here, sum of digits of number will always be 2 when n=0,1,2,3,... Hence, the sum of digits in the number is 2 for any whole number n.