import pathlib,pypdf
from pypdf import PdfWriter

merger = PdfWriter()
for index in range(50):
    major=int(index/7)
    minor=index%4
    for pdf in pathlib.Path(__file__).parent.glob(f"*{major}.{minor}*.pdf"):
        if not pdf.is_file():
            continue
        print(pdf,end='\r')
        merger.append(pdf)

merger.write("merged-pdf.pdf")
merger.close()