Here's another way, where temp
is your list (simplified by @Thomas's advice)
temp2 <- mapply(match, names(temp), strsplit(gsub("^.*\\cell_", "", temp), "_"))
temp2 <- cbind(as.numeric(names(temp2)), as.numeric(temp2))
# [,1] [,2]
# [1,] 1 1
# [2,] 5 2
# [3,] 6826 1
# [4,] 9888 1
# [5,] 9890 2
# [6,] 9892 1
# [7,] 9895 3