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%I #37 Dec 30 2019 12:13:33
%S 1,2,3,6,7,19,34,67,102,115,190,2066,24381,24398,24399,36130540,
%T 409493529,3744514071,17951662018,71184216405
%N Values of n at which the ratio A005132(n)/n sets a new record.
%C See A064621 for associated values of A005132.
%C No other terms < 4.61 * 10^11. - _Jud McCranie_, Dec 29 2019
%H <a href="/index/Rea#Recaman">Index entries for sequences related to Recamán's sequence</a>
%e A005132(7)=20, 20/7 = 2.857..., larger than the ratio for any smaller value of n. So 7 is in the sequence.
%t Block[{s = Nest[Append[#1, If[And[#3 > 0, FreeQ[#1, #3]], #3, #1[[-1]] + #2]] & @@ {#1, #2, #1[[-1]] - #2} & @@ {#, Length@ #} &, {0}, 10^5], t}, t = MapIndexed[#1/First@ #2 &, s]; -1 + Rest@ Map[FirstPosition[t, #][[1]] &, Union@ FoldList[Max, t]] ] (* _Michael De Vlieger_, Dec 29 2019 *)
%Y Cf. A005132, A064621.
%K nonn,more
%O 1,2
%A _Jud McCranie_, Sep 26 2001
%E Two more terms from _John W. Layman_ and _N. J. A. Sloane_, Oct 12 2001
%E Offset changed, a(19)-a(20) from _Jud McCranie_, Dec 28 2019
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