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Values of A005132(n) at which the ratio A005132(n)/n sets a new record.
3

%I #31 Dec 30 2019 12:12:40

%S 1,3,6,13,20,62,113,224,367,494,833,9169,131313,155719,180118,

%T 280766754,3454917187,31685027464,152431947617,629621648241

%N Values of A005132(n) at which the ratio A005132(n)/n sets a new record.

%C See A064622 for associated values of n.

%C No other terms < 4 * 10^12. - _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.

%t Block[{s = Nest[Append[#1, If[And[#3 > 0, FreeQ[#1, #3]], #3, #1[[-1]] + #2]] & @@ {#1, #2, #1[[-1]] - #2} & @@ {#, Length@ #} &, {0}, 200000], t}, t = MapIndexed[#1/First@ #2 &, s]; Rest@ Map[s[[FirstPosition[t, #][[1]] ]] &, Union@ FoldList[Max, t]] ] (* _Michael De Vlieger_, Dec 29 2019 *)

%Y Cf. A005132, A064622.

%K more,nonn

%O 1,2

%A _Jud McCranie_, Sep 26 2001

%E Offset changed, a(19)-a(20) from _Jud McCranie_, Dec 28 2019