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A262059 Least integer k such that k^(1/3)/log(k) exceeds n. 3
2, 4913, 29410, 96854, 236916, 484596, 879483, 1465239, 2289183, 3401984, 4857388, 6712006, 9025131, 11858570, 15276512, 19345406, 24133846, 29712478, 36153913, 43532644, 51924974, 61408954, 72064316, 83972419, 97216198, 111880113, 128050105, 145813554, 165259239, 186477301, 209559205 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..31.

MAPLE

A262059val := proc(k)

    Digits := 100 ;

    evalf(root[3](k)/log(k)) ;

end proc:

A262059lims := proc(n, lowk, highk)

    local vallow, valhigh, midk, valmid ;

    vallow := A262059val(lowk) ;

    valhigh := A262059val(highk) ;

    if valhigh > n and vallow <= n and highk= lowk+1 then

        return highk;

    else

        midk := floor((lowk+highk)/2) ;

        valmid := A262059val(midk) ;

        if valmid < n then

            return procname(n, midk, highk) ;

        else

            return procname(n, lowk, midk) ;

        end if;

    end if;

end proc:

A262059 := proc(n)

    local lowk, highk, p ;

    if n = 1 then

        return 2;

    end if;

    for p from 0 do

        lowk := 10^p ;

        highk := 10^(p+1) ;

        if A262059val(highk) >=n then

            return A262059lims(n, min(2, lowk), highk) ;

        end if;

    end do:

end proc: # R. J. Mathar, Oct 22 2015

MATHEMATICA

f[n_] := f[n] = Block[{k = f[n - 1]}, While[n > k^(1/3)/Log[k], k++]; k]; f[1] = 2; Array[f, 40]

PROG

(PARI) a(n) = {my(k = 2); while(sqrtn(k, 3)/log(k) <= n, k++); k; } \\ Michel Marcus, Sep 10 2015

CROSSREFS

Cf. A088346, A262058, A262060.

Sequence in context: A195002 A203756 A232712 * A153737 A078933 A064029

Adjacent sequences:  A262056 A262057 A262058 * A262060 A262061 A262062

KEYWORD

nonn

AUTHOR

Robert G. Wilson v, Sep 09 2015

STATUS

approved

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Last modified August 24 02:32 EDT 2019. Contains 326260 sequences. (Running on oeis4.)