import numpy as np
import matplotlib.pyplot as plt
cyan = np.array([(x*0, x*1, x*1, 255) for x in range(256)])
input_array = np.arange(0, 0.8, 0.05).reshape(4, 4)
input_array = (input_array * 256).astype(int)
colour_array = cyan[input_array]
plt.imshow(colour_array)
plt.show()