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A038025 Winner of n-th Littlewood Frog Race. 8
1, 1, 1, 1, 4, 1, 1, 1, 1, 9, 10, 1, 12, 1, 1, 9, 1, 1, 1, 1, 4, 21, 22, 1, 24, 25, 1, 27, 27, 1, 1, 1, 16, 1, 16, 35, 32, 1, 38, 9, 10, 25, 33, 25, 1, 45, 27, 1, 25, 49, 44, 25, 24, 1, 1, 9, 34, 27, 1, 49, 24, 1, 58, 57, 64, 49, 8, 49, 65, 51, 48, 49, 72, 69, 68 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

For 0 < k <= n, gcd(n,k) = 1, let P(n,k) be the smallest prime of the form a*n+k, with a >= 0. "Frog" k0 is said to win "race" n if P(n,k0) is largest of the phi(n) values P(n,k).

In case of draws of P(n,k) values take the largest k.- R. J. Mathar, Jul 26 2015

LINKS

Table of n, a(n) for n=1..75.

MAPLE

A038025P := proc(n, k)

    local a;

    for a from 0 do

        if isprime(a*n+k) then

            return a;

        end if;

    end do:

end proc:

A038025 := proc(n)

    local a, phimax, phi, k ;

    a :=0 ;

    phimax := 0 ;

    for k from 1 to n do

        if igcd(k, n) = 1 then

            phi := A038025P(n, k) ;

            if phi >= phimax then

                a := k;

                phimax := phi;

            end if;

        end if;

    od;

    a ;

end proc:

seq(A038025(n), n=1..100) ; # R. J. Mathar, Jul 26 2015

CROSSREFS

Cf. A038026, A038029 (records).

Sequence in context: A119350 A016528 A056623 * A079982 A265143 A181873

Adjacent sequences:  A038022 A038023 A038024 * A038026 A038027 A038028

KEYWORD

nonn

AUTHOR

Christian G. Bower from a problem by David W. Wilson

STATUS

approved

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Last modified June 25 07:18 EDT 2019. Contains 324347 sequences. (Running on oeis4.)