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A204315 n such that floor(n^(1/4)) divides n. 0
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76, 78, 80, 81, 84, 87, 90, 93, 96, 99, 102, 105, 108, 111, 114, 117, 120, 123, 126 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..64.

FORMULA

Let P(x)=(4/3)x^3+9x^2+(68/3)x+15. Let m>=0 and suppose n=P(k)-m>P(k-1). Then a(n)=k^4+8k^3+24k^2+(32-m)k+m-15.

MAPLE

isA204315 := proc(n)

    if modp(n, floor(root[4](n))) = 0 then

        true ;

    else

        false ;

    fi ;

end proc:

for n from 1 to 130 do

    if isA204315(n) then

        printf("%d, ", n) ;

    end if;

end do: # R. J. Mathar, Sep 10 2017

CROSSREFS

Cf. A079645.

Sequence in context: A235986 A080197 A115847 * A032966 A122937 A246076

Adjacent sequences:  A204312 A204313 A204314 * A204316 A204317 A204318

KEYWORD

nonn

AUTHOR

Benoit Cloitre, Jan 14 2012

STATUS

approved

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Last modified July 15 22:48 EDT 2019. Contains 325061 sequences. (Running on oeis4.)