so each person in a greek male orgy wants to have sex with everyone attending, all of them will form a pair at least once, in order they will form these amount of pairs, the first one 22 pairs, the second one 21 and on and on
22+21+20+19+18+17+16+15+14+13+12+11+10+9+8+7+6+5+4+3+2+1 = 253
so...