1, 2, 3, 4, 6, 7, 9, 12, 14, 18, 21, 28, 36, 42, 63, 84, 126, 252
2x2x3x3x7=252
The numbers for the vertebrates are 252.
12 and 252
252
787885
There are several pairs of numbers that multiply to get 252. One example is 12 and 21, since 12 x 21 = 252. Another pair is 9 and 28, as 9 x 28 also equals 252.
126 and 252, among others.
252
How about 2 times 126 = 252 as one example
1+251
If there are three consecutive numbers which sum to 252, you can find the answer by merely dividing 252 by 3. Then take that number and the two on either side of it. So we get 84, then we take it's neighbors 83 and 85 and we're done. 252.
252 2x126 2x2x63 2x2x3x3x7