Find the minimum value of such that the sum of positive integers is 2018 and any positive integer less than or equal to 2018 is the sum of some of these integers.
Bonus: Generalize this for the sum of integer
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Ten summands are not enough, since we can form at most 2 1 0 = 1 0 2 4 distinct sums out of them. But 11 works: We can write 2 0 1 8 = 9 9 5 + 5 1 2 + 2 5 6 + 1 2 8 + 6 4 + 3 2 + 1 6 + 8 + 4 + 2 + 1
Any positive integer n < 1 0 2 4 can be written uniquely as a sum of powers of 2, up to 512, and any n with 2 0 1 8 ≥ n ≥ 1 0 2 4 can be written as n = 9 9 5 + ( a sum of powers of 2 up to 512 ) . Thus the answer is 1 1 .
In general, n is the number of digits of N in base 2.
A charming problem that I have never seen in this form before. Thank you!