colorful illustration of a large number twenty one, overlapping each other
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Overlays

The powers of two are all numbers of the form 2^k, where k is an integer greater than or equal to 0.

A number is called a series sum if it is the sum of two or more consecutive integers. For example: 34 is a series sum because 7+8+9+10=34.

Challenger

What is the smallest number that is both a power of two and a series sum? If no such number exists, give 0.

Mastermind

What is the smallest positive integer that is neither a power of two nor a series sum? If no such number exists, give 0.