by Ma3tt » Wed Dec 27, 2006 9:51 am
One hundred [and] twenty-one is a square and is the sum of three consecutive primes (37 + 41 + 43). There are no squares besides 121 known to be of the form 1 + p + p2 + p3 + p4, where p is prime (3, in this case). There are only two other squares known to be of the form n! + 1.
It is also a star number and a centered octagonal number.
In base 10, it is a Smith number since its digits add up to the same value as its factorization (which uses the same digits) and as a consequence of that it is a Friedman number. But it can not be expressed as the sum of any other number plus that number's digits, making 121 a self number.
Thanks Wikpedia!
It is also a star number and a centered octagonal number.
In base 10, it is a Smith number since its digits add up to the same value as its factorization (which uses the same digits) and as a consequence of that it is a Friedman number. But it can not be expressed as the sum of any other number plus that number's digits, making 121 a self number.
Thanks Wikpedia!
Be Good
1967 Siesta del Sobrino "Standy"
If you lived here... you would be home by now.
http://www.Camp-Cook.com
1967 Siesta del Sobrino "Standy"
If you lived here... you would be home by now.
http://www.Camp-Cook.com
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Ma3tt - Dutch Oven GURU
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