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> Just Math (1)> Science> Algorithms
Before trying the problem "note your opinion as to whether the observed pattern is known to continue, known not to continue, or not known at all."

After row 1, row n is obtained by inserting n between every pair of consecutive numbers that sum to n.

row 1:                  1 1
row 2:                 1 2 1
row 3:               1 3 2 3 1
row 4:            1 4 3  2  3 4 1
row 5:        1 5 4  3 5 2 5 3 4 5 1
row 6:   1  6  5 4  3 5  2  5  3  4 5  6 1
row 7: 1 7 6 5 4 7 3 5 7 2 7 5 3 7 4 5 6 7 1
The number of numbers in each row are 2, 3, 5, 7, 11, 13, 19...

Will they always be prime?

(No Solution Yet, 3 Comments) Submitted on 2017-09-19 by Jer   
Difficulty: 1 of 5 Bonus: What am I? (in Riddles) Rating: 2.03
I have keys that open no locks,
I have space, but you cannot fill it,
You can enter, but you cannot leave.
What am I?
(Solution Posted, 51 Comments) Submitted on 2004-05-10 by Popstar Dave   
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