$t_title is "491"
$t_adjust_path is "/~caldwell/curios/"
$t_class is "prime"
$short is "491"
$nunber_id is "4088"
$t_meta['description'] is "One of many pages of prime number
curiosities and trivia. This page discusses 491
Come explore a new prime today!"
The smallest irregular prime having an irregularity index of 3. [Noe]
491 is a Sophie Germain prime. 491 is also a divisor
of a Generalized Fermat Number, as 491 * (2^123281+1)
divides GF(123280,10) = 10^(2^123280) + 1. [Carmichael]
10000^491-491 is the smallest titanic prime of form 10000^n-n, where n is prime. [Loungrides]
The sum of first two Lychrel numbers is prime, i.e., 196+295. [Loungrides]
It is conjectured that 491 is the smallest prime
not of the form x3 + y3
+ 2z3. [Wesolowski]
(There are 5 curios for this number that have not yet been approved by an editor.)
Printed from the PrimePages <primes.utm.edu> © G. L. Honaker and Chris K. Caldwell