Are ther options???
it wud get 500 times simpler.....
n balls are picked, one by one from four urns each containing n identical balls of green, red, white and blue colours. The number of ways, when no two consecutive pickings are from same urn and balls of all the colours are picked,
i know that too
i want the nice big subjective method for this one( thats why dint take the trouble to post the options)