[seqfan] Methodically filling successive squares and primes with N
Eric Angelini
Eric.Angelini at kntv.be
Wed Jun 16 11:56:50 CEST 2010
Hello seqFans,
We want the successive squares to be replaced by sums in this way:
n = 1 2 3 4 5 6 7 8 9 10 11 12 ...
n^2= 1 4 9 16 25 36 49 64 81 100 121 144
- - - -- -- -- -- -- -- --- --- ---
Sum 1 4 2 3 6 11 14 16 18 22 26 30
+ + + + + + + + + +
7 5 9 12 15 17 19 24 27 32
+ + + + + + + + +
8 10 13 20 31 21 25 28 33
+ + + +
23 29 40 49
Thus, to complete a sum, we always use the smallest available positive
integer not used so far and not leading to a contradiction.
The sequence arising from this could be (this is a permutation of N):
Sq = 1,4,2,7,3,5,8,6,9,10,11,12,13,14,15,20,16,17,31,18,19,21,23,...
The same algorithm can be used to "fill the Primes":
2 3 5 7 11 13 17 19 23 29 31 ...
- - - - -- -- -- -- -- -- --
2 3 1 7 5 13 8 19 11 14 10
+ + + + + +
4 6 9 12 15 21
... producing:
Pr = 2,3,1,4,7,5,6,13,8,9,19,11,12,14,15,10,21,...
Neither "Sq" nor "Pr" are in the OEIS. If someone could check, extend
those seq and submit them (in september -- if they are of interest),
it would be nice.
Best,
É.
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