Sure, and then when you say this;
You understand from the jump that you're trying to make this a more routine and/or longer lasting episode. You want a significantly more in-depth tickle experience that the rest of them seem to.
And before the entire threatd gets its feeling hurt; it's fine that you want that. Nobody is accusing you of being a pervert for wanting that.
I am merely explaining to you that it'll almost certainly never happen with this group of friends - without something along the lines of you explaining it outright or something- because you explicitly want something the rest of them seemingly do not. You need to either be willing to change up the dynamic with some of them to obtain tha, which comes with its own risk-reward situations, or go and specifically seek a "strictly platonic tickling" relationship with someone who explicitly wants the same as well.
I'm not trying to imply "normies don't ever tickle each other in the wild!". I'm saying they do and it's over in a few seconds, minutes tops, and then the moment passes. You want more/prolonged moments, which inherently make it a step beyond a "normal vanilla tickle experience". To reiterate again, this isn't "bad". But it is a different dynamic all the same.