agbdmrbirdyface has a very large circular chandelier in his aviary, with 2015 spots for light bulbs. Each of the spots is numbered consecutively from 1 to 2015. He is installing new light bulbs in his chandelier, so at the start, his chandelier has no light bulbs in any of the spots. agbdmrbirdyface wants to install light bulbs in his chandelier according to the following rule: for the nth iteration of this rule, agbd will install n light bulbs in the first n empty lightbulb spots after the n-1th iteration, starting with the first empty lightbulb spot after the n-1th iteration of the rule is complete. After this is complete, he will skip one lightbulb spot. .

agbd will keep applying this rule until all the lightbulb holders are full, even if he has to go back around the circle again to install more light bulbs. If agbd installs the first lightbulb according to the rule in spot number 1, which spot is the last to be filled with a lightbulb?