# A336720 (b-file synthesized from sequence entry) 1 3 2 7 3 31 4 127 5 8191 6 131071 7 524287 8 2147483647 9 4432676798593 10 2305843009213693951 11 57912614113275649087721 12 618970019642690137449562111 13 162259276829213363391578010288127 14 170141183460469231731687303715884105727 15 79638304766856507377778616296087448490695649