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Infinite sequence of signed integers where each is chosen to be as small as possible (in absolute value) subject to the condition that for every k >= 1, all the k(k+1)/2 numbers in the triangle of differences of the first k terms are distinct; in case of a tie, preference is given to the positive value.
2

%I #7 Sep 30 2019 13:10:27

%S 1,-1,2,-3,4,-6,8,-4,6,-9,16,-7,19,-11,17,-14,9,-28,11,-16,13,-20,15,

%T -19,18,-18,27,-24,31,-21,30,-35,38,-32,21,-46,32,-22,44,-40,34,-38,

%U 46,-39,36,-41,47,-43,42,-44,43,-55,50,-42,52,-45,57,-53,62,-57,59

%N Infinite sequence of signed integers where each is chosen to be as small as possible (in absolute value) subject to the condition that for every k >= 1, all the k(k+1)/2 numbers in the triangle of differences of the first k terms are distinct; in case of a tie, preference is given to the positive value.

%C This sequence is a signed variant of A327460.

%H Rémy Sigrist, <a href="/A327887/b327887.txt">Table of n, a(n) for n = 1..5000</a>

%H Rémy Sigrist, <a href="/A327887/a327887.txt">C# program for A327887</a>

%F Apparently, abs(a(n)) ~ n as n tends to infinity.

%e The difference table for the first 8 terms is:

%e 1 -1 2 -3 4 -6 8 -4 ...

%e -2 3 -5 7 -10 14 -12 ...

%e 5 -8 12 -17 24 -26 ...

%e -13 20 -29 41 -50 ...

%e 33 -49 70 -91 ...

%e -82 119 -161 ...

%e 201 -280 ...

%e -481 ...

%e ...

%o (C#) See Links section.

%Y Cf. A327460.

%K sign

%O 1,3

%A _Rémy Sigrist_, Sep 29 2019