I will be the voice of dissent. You’re not into math. You’re into humanities/social sciences. There is zero reason you need to study calculus for that, much less AP calculus, and really AP stats would be a far more useful class for you and your interests. Will not taking AP Calc keep you out of Brown? I seriously doubt your acceptance/rejection will come down to a single class - any class. Yes, they want to see rigor - and you’ve got that through your other APs. Personally, I think you are fine. You may or may not get into Brown (or other top school), but if you have an overall rigorous schedule, great grades, strong ECs, I feel it is very unlikely that a lack of AP Calc will be the deciding factor, especially for a non-STEM major. I just don’t see an AO reading your application and being like, “Wow, he/she is fantastic and a perfect fit! Oh wait…he/she only took Calc with Apps and not AP Calc…Damn, that changes my ENTIRE opinion about his/her viability as an applicant!” I just don’t think so - not for a non-STEM major, anyway. And even if they do, there are literally HUNDREDS of other great colleges out there who will love you, with or without AP calc. I personally would not sweat this at all.
(As an aside, I have two MAs and a PhD and have NEVER taken a single calculus class of any sort in my entire life, so I may be biased, but I also fully believe that academic success is possible without calc 
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