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%I #7 Oct 15 2013 22:31:32
%S 2,3,5,7,6,9,20,12,14,19,22,41,18,55,28,33,37,58,36,50,59,65,57,66,78,
%T 110,118,109,114,108,199,129,146,145,188,164,278,246,265,171,195,250,
%U 193,194,216,313,430,380,429,291,257,293,290,258,639,391,411,415,572
%N Smallest number such that A076228(a(n)) = n.
%F a[n]=Min{x; A076228[x]=n]}
%e n=6:a[6]=9 because first in iteration list started with 9, i.e. in {9, 28, 14, 7, 22, 11, 34, 17, 52, 26, 13, 40, 20, 10, 5, 16, 8, 4, 2, 1}, occurs first n=six sinking below iv=9: at {7, 5, 8, 4, 2, 1}.
%t f[x_] := (1-Mod[x,2])*(x/2)+(Mod[x,2])*(3*x+1); f[1]=1; f0[x_] := Delete[FixedPointList[f,x],-1] f1[x_] := f0[x]-Part[f0[x],1] g[x_] := Count[Sign[f1[x]],-1] t=Table[0,{256}]; Do[s=g[n]; If[s<257&&t[[s]]==0,t[[s]]=n],{n,1,1000}]; t
%Y Cf. A006370, A074473, A076228.
%K nonn
%O 1,1
%A _Labos Elemer_, Oct 01 2002
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