I’m looking for a neater solution than the seq_counter() function I wrote.
It seems to me that there should be something shorter and more readable in R

set.seed(1)
bool_vec <- sample(c(TRUE,FALSE), 10, replace = TRUE)

seq_counter <- function(x){
count <- rep(1,length(x))
n <- 1
for(i in 2:length(count)){
  if(x[i-1]==x[i]){
    count[i] <- count[i]+n
    n <- n+1
  } 
  else {
    n <- 1
  }
}

count
}

cbind.data.frame(bool_vec, seq_cnt=seq_counter(bool_vec))

.

   bool_vec seq_cnt
1      TRUE       1
2     FALSE       1
3      TRUE       1
4      TRUE       2
5     FALSE       1
6      TRUE       1
7      TRUE       2
8      TRUE       3
9     FALSE       1
10    FALSE       2

the function simply calculates the group size, like

 6      TRUE       1
 7      TRUE       2
 8      TRUE       3