Multiples of seven: 14, 2 1, 28, 35, 42, 49, 56, 63, 70, 77, 84, 9 1 98, 105,/kloc-0.

The above is a multiple of 7 to 1 19. It can be seen that the law is that adding "7" after each multiple is a multiple of 7, and so on.

Numbers with seven are: 7, 17, 27, 37, 47, 57, 67, 77, 87, 97, 107,17, 127,/.

Interesting knowledge:

Among natural numbers, 7 is the most special and interesting number, and 7 is a prime number in natural numbers. In life, 7 is widely used.

Mathematics: Scientists think that 7 is the most special number, and they also find that in calculation, 7 divided by 1, 2, 3, 4, 5, 6, respectively, are infinite circulating decimals. The cycle node of the decimal part is in the seventh place. The number of the decimal part will not change, but the position will change.

Life: There are 7 days in a week, 7 beads in each row of abacus, 7 colors in spectrum, and 7 puzzles in variety. A general block object is divided into seven blocks. If you don't believe me, you can pay close attention to the details of life. The reasons for it were not known There are seven continents on the earth.

Culture and art: an octave natural scale, guqin seven strings, seven quatrains, the legendary seven fairies.