In reply to SUNODH:
When you have an open bracket set of bins, each range get expanded into a set of individual values with each value getting a bin. b4 creates 43 bins. And if there were duplicate values, they would get removed. In other words only one bin for a particular value gets created.
When you have a fixed size set of bins, the ranges also get expanded into a set of individual values in the order they appear. Duplicate values get retained in the order they appear.
b1[3] would be 3 bins with the first having the first 14 values 79-92, the second getting the next 14 values 93-99 & 110-116, and the third getting the last 15 values 117-130 & 140.
b1[4] would be 4 bins with 10, 10, 10, and 13 values each.