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A346593
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Numbers k such that A006577(k^3) sets a new record.
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4
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2, 3, 6, 7, 14, 15, 25, 41, 45, 71, 79, 153, 233, 235, 470, 503, 707, 741, 1482, 2964, 3039, 3581, 7162, 14324, 27337, 54674, 61683, 123366, 168159, 254251, 302839, 605678, 622699, 947173, 1618687, 3237374, 6474748, 10995401, 13042083, 21767875, 43535750, 48584565
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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s[n_]:=s[n]=(i=0; r=n; While[r!=1, i++; If[EvenQ@r, r=r/2, r=r*3+1]]; i);
lst={}; max=1; Do[t=s[k^3]; If[t>max, AppendTo[lst, k]; max=t], {k, 10^4}]; lst (* Giorgos Kalogeropoulos, Jul 28 2021 *)
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PROG
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(PARI) a6577(n0)={my(n=n0, k=0); while(n>1, k++; n=if(n%2, 3*n+1, n/2)); k};
a346593(limit)={msteps=0; for(k=1, limit, my(m=a6577(k^3)); if(m>msteps, print1(k, ", "); msteps=m))};
a346593(1000000)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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