Bloomberg Philanthropies announced that 305 cities, including Redmond, have submitted ideas in the first-ever Mayors Challenge, a competition to identify bold ideas that solve major challenges and improve city life — and can spread to other cities.

The grand-prize-winning city will receive a $5 million innovation prize; four runner-up cities will receive $1 million each. A selection committee will help Bloomberg Philanthropies identify the 20 finalist cities that will advance to the next stage of the competition.

The ideas generated by these cities were diverse. The two largest categories of ideas were economic development (20 percent) and citizen engagement to spur innovation (20 percent). Other significant categories include customer service (11 percent), sustainability (10 percent), public health (10 percent) and education (9 percent).