Matrix

Noyal wants ‘n’ papers for his event ‘Matrix’. He went to Roy Brothers Shop and found many piles of papers there. The shopkeeper told him that the ith pile contains i^3 papers and costs Rs. i and immediately asked him to take all the alternate piles starting from the last pile to the 1st or 2nd pile (depending on no. of piles being odd or even respectively) to meet his requirements. Now Noyal too