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Binary Primes (Posted on 2004-02-18)

How many primes, written in usual base 10, have digits that are alternating 1s and 0s, beginning and ending with one?

For example (not necessarily prime):
1, 101, 10101, ...

See The Solution Submitted by Aaron

Rating: 3.5000 (2 votes)

Comments: ( You must be logged in to post comments.)

Subject	Author	Date
Puzzle Solution	K Sengupta	2022-08-27 02:20:04
solution	Dej Mar	2011-06-22 05:56:06
re: Another thought	WAyne	2007-09-30 06:26:58
re: Oh god! I read the question wrong.	Brian Wainscott	2004-02-23 15:25:28
OK I swear this is the last time!	Mitch Mullings	2004-02-22 21:01:21
Oh god! I read the question wrong.	Mitch Mullings	2004-02-22 20:59:37
It's me again adding to my previous entry	Mitch Mullings	2004-02-22 20:57:19
It's me! Mwahahahaha. Okay I'll stop now.	Mitch Mullings	2004-02-22 20:54:46
re: No Subject	Brian Wainscott	2004-02-18 19:03:50
No Subject	e.g.	2004-02-18 15:25:11
Second thought	Larry	2004-02-18 14:25:58
Another thought	Brian Wainscott	2004-02-18 14:25:17
First thought	Brian Wainscott	2004-02-18 14:20:32

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