How to make a random-like tool to generate numbers from set like [1, 4, 7, 10, 15, ...] not from sequence [1-1000]?

[random 4]
|
[sel 0 1 2 3]
| | | |
| | | [6(
| | [4(
| [20(
[10000(

does that do what you need? you can use tabread on larger sets, or reconfigurable sets.

here's a couple of options (see attached)

http://www.pdpatchrepo.info/hurleur/random_selection.pd

Great. Thanks.