arange

m = np.arange(3,15,2)
print(m) # [3,5,7,9,11,13]

n = np.arange(2,10,1)
print(n) # [2,3,4,5,6,7,8,9,10]

# np.arange != range >>> np.arange(3)
array([0, 1, 2])
>>> np.arange(3.0)
array([ 0.,  1.,  2.])
>>> np.arange(3,7)
array([3, 4, 5, 6])
>>> np.arange(3,7,2)
array([-3, 5])