Q: Domestic bees make their honeycomb by starting with a single hexagonal cell, then forming ring after ring of hexagonal cells around the initial cell, as shown. The numbers of cells in successive rings form an arithmetic sequence. a. Write a rule for the number of cells in the nth ring. b. What is the total number of cells in the honeycomb after the 9th ring is formed?
For making rule(formulae) for counting the number of cells in the nth ring, we would need the values for the following variables
a=?
d=?
I started counting cells from the initial ring and set a=1 and d=6 and start counting from the 1st ring and set a=7 and d=6 but I have got wrong answers both times then what is the correct way to find the values for variables to put in the following equation and would we count initial cell as a part of the ring?
An=a+(n-1)d