Almost perfect numbers refer to numbers where
σ(x) = 2x - 1, where σ is the sum of divisors function. Any number in the form 2n is almost perfect because
σ(2n) = 1 + 2 + 4 + ... + 2n = 2n+1-1 = 2(2n) - 1.
It is unknown whether any other almost perfect numbers exist.
Yes. The only known almost perfect numbers are the powers of 2. 32 = 2^5 is an almost perfect number. It has not yet been proved whether {x: x = 2^n for n in N} = {x: x is an almost perfect number}.
No. The only known almost perfect numbers are the powers of 2, namely 1, 2, 4, 8, 16, 32, ...
There are infinitely many perfect numbers so they cannot all be listed.
There is a one-to-one relationship between even perfect numbers and Mersenne primes. It is unknown whether there are any odd perfect numbers.
There are two perfect numbers, 6 and 28, that are less than 100.
An almost perfect number is a natural number n such that the sum of all divisors of n is equal to 2n - 1.
Yes. The only known almost perfect numbers are the powers of 2. 32 = 2^5 is an almost perfect number. It has not yet been proved whether {x: x = 2^n for n in N} = {x: x is an almost perfect number}.
No. The only known almost perfect numbers are the powers of 2, namely 1, 2, 4, 8, 16, 32, ...
The duration of Almost Perfect is 1800.0 seconds.
Perfect numbers are numbers where all the factors add to that number. For example 6's factors are 1,2, and 3 and 1+2+3=6. Therefore the next perfect number isn't until 28 which is 1,2, 4, 7, 14 where 1+2+4+7+14= 28 An almost perfect number is a number which, when adding all of its proper divisors (all divisors except himself), gives you one less, or one more then the number itlself. Up to now all known almost perfect numbers are 2^n. So to answer your question, the 2 almost perfect numbers between 5 and 20 are 8 and 16. Divisors of 8: 1,2,4 -----> 1+2+4=7 Divisors of 16: 1,2,4,8 -----> 1+2+4+8=15
6 and 28 are perfect numbers.
there are no perfect numbers instead there are perfect cubes, perfect squares, natural numbers, whole numbers, integers, rational numbers, irrational numbers, and real numbers. If you want natural no. they are 21, 22, 23, 24, 25, 26, 27, 28, and 29.
Almost Perfect - Torchwood - was created in 2008.
Almost Perfect ended on 1996-10-30.
Almost Perfect was created on 1995-09-17.
The duration of An Almost Perfect Affair is 1.55 hours.
No. The only perfect numbers less than 100 are 6 and 28. All known perfect numbers are even - it is unknown whether there are odd perfect numbers.