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%I #14 Feb 20 2020 15:42:38
%S 1,5,5,2,7,15,11,4,13,25,17,6,19,35,23,8,25,45,29,10,31,55,35,12,37,
%T 65,41,14,43,75,47,16,49,85,53,18,55,95,59,20,61,105,65,22,67,115,71,
%U 24,73,125,77,26,79,135,83,28,85,145,89,30,91,155,95,32,97,165,101,34,103,175
%N First differences of A154293.
%F a(n) = A287733(n)/6.
%t Select[Accumulate[Range[0,300]]/6,IntegerQ]//Differences (* _Harvey P. Dale_, Feb 20 2020 *)
%Y Cf. A069497, A108782, A154293, A287733.
%K nonn
%O 1,2
%A _Greg Huber_, May 31 2017