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Rearrangement of natural numbers so that every term is relatively prime to the sum of its neighbors.
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%I #4 Dec 05 2013 19:55:37

%S 1,2,4,3,6,8,5,9,11,7,12,10,15,13,14,16,17,19,18,22,21,24,20,23,25,26,

%T 28,27,30,32,29,31,34,36,33,35,38,40,39,37,41,42,44,43,45,46,48,49,47,

%U 50,52,51,54,56,53,55,58,60,61,57,63,59,62,64,65,67,66,70,71,68,72,69

%N Rearrangement of natural numbers so that every term is relatively prime to the sum of its neighbors.

%C If a(n) = k, define the dislocation of k to be Absolute[k-n]. Conjecture: The maximum value of dislocation < 5.

%C The conjecture first fails at a(169) = 164. In the first 18000 terms, the largest dislocation is 8. - _David Wasserman_, Jan 17 2005

%Y Cf. A075376.

%K nonn

%O 1,2

%A _Amarnath Murthy_, Sep 20 2002

%E More terms from _David Wasserman_, Jan 17 2005