R code to provide an answer to stackoverflow question at https://stackoverflow.com/q/52613778/3135417

group_until.R

# https://stackoverflow.com/q/52613778/3135417

# Function to keep track of diff changes along the V1 column
get_ids <- function(x) {
  vrle <- rle(cummin(x))$lengths
  rep(1:length(vrle), vrle)
}

# Thesis data
thesis <- data.frame(V1=c(8628, 8626, 8624, 8622, 8620, 8618,
                          8576, 8574, 8572, 8570, 8568, 8566,
                          8422, 8420, 8418),
                     V2=c(0.0191929, 0.0383858, 0.0575787,
                          0.0767716, 0.0959645, 0.1151574,
                          0.1343503, 0.1535432, 0.1727361,
                          0.191929, 0.2111219, 0.2303148, 0.2495077,
                          0.2687006, 0.2878935))

# Split the original data.frame.
# Use the get_ids function to segment the V1 column.
# If the diff changes stop decrementing by 2, then the id value is incremented
chunks <- split(thesis, get_ids(c(-2, diff(thesis$V1))))

# Filtering for sub data.frames with more than 2 rows
Filter(function(df) nrow(df) > 2, chunks)