### About the Number 41 (forty-one)

While working on a nBAB for the number 43, MathBabbler noticed that 43 was a "twin prime" of number 41.

```   MathBabbler Number Analyst (MBNA) output:
=========================================
41 is a natural, whole, integer
41 is odd
41 is unhappy
41 is not a Harshad number
41 is prime
...Cousin prime with 37
...Sexy prime with 47
...Sophie Germain prime with 83
...Twin prime with 43
...Pythagorean
...Super
...prime triplet {37, 41, 43}
...prime triplet {41, 43, 47}
41 is undulating
41 in octal is 051
41 in hexadecimal is 0x29
41 in binary is 101001 (is odious)
41 nearest square numbers: -5...8 (36 ...49 )
sqrt(41) = 6.40312
ln(41) = 3.71357
log(41) = 1.61278
41 reciprocal is .02439024390243902439024390243902
41! is 3.34525e+49
41 is 13.0507 Pi years
41 is 2 score and 1 year
```

`41` written as a Roman numeral is `XLI`.

Wikipedia tidbits...

```   42 + 52 = 41                     # sum of two squares
2 + 3 + 5 + 7 + 11 + 13 = 41     # sum of 1st six primes
11 + 13 + 17 = 41                # sum of three consecutive primes
??? adding up the sums of divisors for 1 through 7 yields 41 ???
```

Another Wikipedia tidbit...

```   Euler first noticed (in 1772) that the quadratic polynomial

P(n) = n2 + n + 41

is prime for all non-negative integers less than 40. The primes
for n = 0, 1, 2, 3... are 41, 43, 47, 53, 61, 71... The differences
between the terms are 2, 4, 6, 8, 10... For n = 40, it produces a
square number, 1681, which is equal to 41 * 41, the smallest
composite number for this formula. In fact if 41 divides n
it divides P(n) too.
```

MathBabbler created this nBAB when he was 51 years young. 51 in base-8 (octal) equals `41`.

This nBAB about the number `41` was created as a result of creating a nBAB about the number `43` and the average of `41` and `43` is `42` (i.e. the "Answer to Life, the Universe, and Everything")

The Wikipedia claims the phrase "let it be" is sang `41` times in the song "Let It Be."

Added a song titled `#41` by the Dave Matthews Band to Songs With Numbers in Their Titles.

Creator: Gerald Thurman [gthurman@gmail.com]
Created: 23 November 2008 (nBAB# 76; BAB# 1924) 