def _log10_lb(c, correction={'1': 100, '2': 70, '3': 53, '4': 40, '5': 31, '6': 23, '7': 16, '8': 10, '9': 5}):
 if (c <= 0):
  raise ValueError('The argument to _log10_lb should be nonnegative.')
 str_c = str(c)
 return ((100 * len(str_c)) - correction[str_c[0]])

def _log10_lb ( c , correction = { '1' : 100 , '2' : 70 , '3' : 53 , '4' : 40 , '5' : 31 , '6' : 23 , '7' : 16 , '8' : 10 , '9' : 5 } ) : if ( c <= 0 ) : raise ValueError ( 'The argument to _log10_lb should be nonnegative.' ) str_c = str ( c ) return ( ( 100 * len ( str_c ) ) - correction [ str_c [ 0 ] ] )
compute a lower bound for 100*log10(c) for a positive integer c .