Code to verify the sequence => difference => factorial

README.md

run on replit

seqdiffFac.py

def setdiff_fac_verify(start, stop, power):
  lst = list(range(start, stop+1))
  if len(lst) < power + 2:
    raise ArithmeticError('list too small(' + (power+2) + ' terms required, got ' + len(lst) + ')')
  nlst = []
  for i in lst:
    nlst.append(i**power)
  def get_diffs(seqlst, diffd):
    print(diffd, seqlst)
    if diffd == power:
      return seqlst
    else:
      dlst = []
      for i in range(1, len(seqlst)):
        dlst.append(seqlst[i]-seqlst[i-1])
      diffd += 1
      return get_diffs(dlst, diffd)
  def fac(x):
    if x == 0:
      return 1
    else:
      return x * fac(x-1)
  endlst = get_diffs(nlst, 0)
  return all(i == endlst[0] for i in endlst) and endlst[0] == fac(power)

st = input('start: ')
sto = input('stop: ')
p = input('power: ')
result = setdiff_fac_verify(int(st), int(sto), int(p))
print(result)