A085330 Where records occur in A085068.

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

Table of n, a(n) for n=1..24.

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

Cf. A085068, A085071, A085328.

Sequence in context: A208583 A197310 A266525 * A222628 A287032 A136368

Adjacent sequences: A085327 A085328 A085329 * A085331 A085332 A085333

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