RosettaCodeData/Task/Arithmetic-derivative/Python/arithmetic-derivative.py

20 lines
486 B
Python

from sympy.ntheory import factorint
def D(n):
if n < 0:
return -D(-n)
elif n < 2:
return 0
else:
fdict = factorint(n)
if len(fdict) == 1 and 1 in fdict: # is prime
return 1
return sum([n * e // p for p, e in fdict.items()])
for n in range(-99, 101):
print('{:5}'.format(D(n)), end='\n' if n % 10 == 0 else '')
print()
for m in range(1, 21):
print('(D for 10**{}) divided by 7 is {}'.format(m, D(10 ** m) // 7))