5, Prime Number, Fibonacci Number, Deficient number
Sexy Prime (Primes p such that p + 6 is also prime)
5 = 12 − 34 + 5 − 67 + 89
5 = 98 − 76 + 5 − 43 + 21
5 = 0^6 − 1^9 + 2^8 − 3^7 + 4^5 + 5^4 + 6^3 + 7^1 + 8^2 + 9^0
2 = 1^2 + 2^2
5 = (4 × 4 + 4)÷ 4 = (44 − 4!) ÷ 4
54 = 24+24+34+44+44
25 - 1 = 31
5 = 2 + 3 , Sum of the first 2 primes
For every integer n, n^5 - n is divisible by 5
Number k such that (7*10^k + 71)/3 is prime
Number k such that (k! + 3)/3 is prime
Numbers k such that 2^k + 9 is prime. (41)
Numbers k such that (35*10^k - 11)/3 is prime
Numbers k such that (8*10^k + 49)/3 is prime.
Prime quadruple: numbers k such that k, k+2, k+6, k+8 are all prime.
Odd number n such that 3^n+1 is a sum of two squares, \( 3^5 + 1 = 10^2 + 12^2 \)
7 = Integer partitions of 5
Number of ways to partition 2n+1 into distinct positive integers, n = 3 ( 7 = 1+6 = 2+5 = 3+4 = 1+2+4 )
Fermat prime: primes of the form 2^(2^k) + 1, k = 1
Numbers of edges of regular polygon constructible with unmarked straightedge and compass.
Number of intersections of diagonals in the interior of a regular 5-gon.
Prime whose binary representation is also the decimal representation of a prime.
Sqrt(5) = 2 + 1/(4 + 1/(4 + 1/(4 + 1/(4 + 1/(4 + 1/(4 + 1/(4 + 1/(4 + 1/(4 + 1/(4 + 1/(4 + 1/(4 + 1/(4 + 1/(4 + 1/(4 + 1/(4 + 1/(4 + 1/...)))))))))))))))))
Factors: 1, 5
Representations, Binary to Hexadecimal:
101_2
12_3
11_4
10_5
5_6
5_7
5_8
5_9
5_11
5_12
5_13
5_14
5_15
5_16
Undergraduate Texts in Mathematics
Graduate Studies in Mathematics
