You can use
text = re.sub(r'n(?=[A-Z0-9])', '', text)
See the regex demo.
Details:
- here, start of a word
n
- a n
letter
(?=[A-Z0-9])
- a positive lookahead that requires an uppercase ASCII letter or a digit to be present immediately to the right of the current location.
See the Python demo:
import re
rx = r"n(?=[A-Z0-9])"
text = "nFamily n49 new nTom"
print( re.sub(rx, '', text) )
# => Family 49 new Tom
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