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User:Jean-Bernard François
$whoami?
I'm Jean-Bernard François (aka infofiltrage) born in France the 03/05/69 & DP Engineer (Engineering Graphics Software).
My current blog is Bondissant (almost art from geometry).
I love number theory, mathematics, and of course OEIS.
I only worked under Debian Linux System with LibreOffice, Inkscape and a LiberKey.
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Collatz | Diophantine | Primes | Number Theory
| Sequence of the Day |
Sequence of the Day for January 2
A004676: Primes written in base 2.
- { 10, 11, 101, 111, 1011, 1101, 10001, ... }
Since 2 is the only even prime, then of course it is the only one that ends in zero in base 2. This highlights the oddity of 2 being the only even prime number.
The Fermat primes (only five are known!) are the only primes with binary weight equal to two: {11, 101, 10001, 10000001, 10000000000001, ...more???}
The repunits (base 2) are the Mersenne primes.
