A058545 Trajectory of 23 under map that sends x to 3x - sigma(x), where sigma(x) is the sum of the divisors of x.
23, 45, 57, 91, 161, 291, 481, 911, 1821, 3031, 5621, 9759, 16261, 29199, 48661, 97321, 180731, 361461, 595359, 914661, 1302543, 1810989, 2732295, 3594645, 4393215, 5513805, 5482215, 6700245, 8913663, 12588669, 19116087, 31171125
Offset: 0