What could be the number encoding algorithm?

Question

reverse engineering

There is a small list of matching real identities and their encoded versions created for the purpose of protection against the selection of successive elements:
100,000 - 45,897,685
100,001 - 46,039,917
100 002 - 108
475 023 100 003 - 94,191,910 100 004 - 108 483 317 100 005 - 107
938 237 100 006 - 104 937 295 100
007 - 108
433 698
100 008 - 102 866
476
100009 - 7129924
100010 - 6539665
100011 - 22487762
And so on.
Does it look like some known algorithm? I tried "pseudo_encrypt" and "pseudo_encrypt24" functions from "PostgreSQL" - they don't work. If there is no solution on the surface, how much would it cost to find it?