Su Dongpo's mathematical poem entitled "Birds Return to the Nest";

Born one after another, three four five six seven eight.

Phoenix birds have fewer birds, pecking at the valley of thousands of stones on earth!

After calculation, "one gives birth to one" is 1+ 1 = 2. "345678, but 3× 4 = 12, 5× 6 = 30, 7× 8 = 56. The sum of the four groups of numbers is exactly 100.