As per given by the question,
There are given that a pennies to make a pattern.
Now,
For written the number of pennies as a sequence,
From the figure,;
In first figure there are only one pennies.
In the second figure, there are three pennies.
In the third figure, there are six pennies.
So,
According to the sequence concept,
In arithmetic sequesnce the terms can be whole number, fraction and decimals.
Then, from the given figure the sequence is;