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A085330
Where records occur in A085068.
3
0, 1, 5, 161, 1772, 3097, 3473, 23084, 38752, 335165, 491729, 38248700, 49050536, 95305397, 1019659805, 1549919921, 2973640172, 4527000701, 6300121204, 10663850980, 30980417576, 40783699961, 57033894608, 409565230433
OFFSET
1,3
LINKS
J. C. Lagarias and N. J. A. Sloane, Approximate squaring (pdf, ps), Experimental Math., 13 (2004), 113-128.
MATHEMATICA
f[n_] := Block[{c = 1, k = 4 n/3}, While[ ! IntegerQ@k, c++; k = 4 Ceiling@k/3]; c]; t = Table[0, {1000}]; Do[ a = f@n; If[a < 101 && t[[a]] == 0, t[[a]] = n; Print[{a, n}]], {n, 0, 21*10^8}] (* Robert G. Wilson v, May 28 2007 *)
PROG
(PARI) f(n)=(4/3)*ceil(n); { a(n) = local(c, k); c=1; k=n; while(frac(f(k))!=0, k=f(k); c++); c } { rec=0; for(n=0, 5*10^5, if(a(n)>rec, rec=a(n); print1(n":"a(n)", "))) }
CROSSREFS
KEYWORD
nonn,more
AUTHOR
N. J. A. Sloane, Aug 13 2003
EXTENSIONS
More terms from Jason Earls, Aug 14 2003
a(12)-a(16) from Robert G. Wilson v, May 28 2007
a(17)-a(24) from Lars Blomberg, Mar 03 2018
STATUS
approved