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As someone who is now 41, I can tell you it is VERY SIGNIFICANT!
Yes!As someone who is now 41, I can tell you it is VERY SIGNIFICANT!
Yes!As someone who is now 41, I can tell you it is VERY SIGNIFICANT!
Forty is young enough to be handsome and fit and old enough to know better, but I have no idea what this has to do with the thread or why I am saying this. Was it not Aristotle who said that a man is smartest at around forty? A lucky very few will peak one day at fifty. Maybe it means that 40 is both handsome and wise, so then, obviously, the sons of Noah got off the ark after forty days at their handsomest and yet very wise.
Wikipedia said:Forty is an octagonal number, and as the sum of the first four pentagonal numbers, it is a pentagonal pyramidal number. Adding up some subsets of its divisors (e.g., 1, 4, 5, 10 and 20) gives 40, hence 40 is a semiperfect number.
Given 40, the Mertens function returns 0. 40 is the smallest number n with exactly 9 solutions to the equation φ(x) = n.
Forty is the number of n-queens problem solutions for n = 7.
Since the greatest prime factor of 402 + 1 = 1601 is prime and obviously more than 40 twice, 40 is a Størmer number.
40 is a repdigit in base 3 (1111) and a Harshad number in base 10.
Negative forty is the temperature at which the Fahrenheit and Celsius scales correspond; that is, −40°F = −40°C. It is referred to as either "minus forty" or "forty below".