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A206476 Numbers n such that n^5 = a^2 + b^3 + c^5 for some positive integers a, b, and c. 0
2, 6, 8, 9, 10, 11, 12, 13, 14, 18, 19, 20, 21, 24, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 59, 60, 61, 62, 64, 65, 66, 67, 68, 69 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Some can be expressed in more than one way.

LINKS

Table of n, a(n) for n=1..55.

EXAMPLE

10^5 = 168^2 + 40^3 + 6^5 = 280^2 + 24^3 + 6^5.

PROG

(Maxima) isA206476(n) := block(

    [a, b, c, v],

    v : false ,

    for c : 1 while c < n and not v do (

        for b : 1 while b^3+c^5 < n^5 and not v do (

            for a : isqrt(n^5-c^5-b^3) while a^2+b^3+c^5 <= n^5 and not v do (

                if equal(a^2+b^3+c^5, n^5) then v : true

            )

        )

    ),

    return(v)

)$

for n : 1 thru 100 do (

    if equal(isA206476(n), true ) then print(n)

)$ /* R. J. Mathar, Feb 27 2012 */

CROSSREFS

Sequence in context: A320573 A003610 A201776 * A077477 A095879 A342751

Adjacent sequences:  A206473 A206474 A206475 * A206477 A206478 A206479

KEYWORD

nonn

AUTHOR

Carmine Suriano, Feb 08 2012

STATUS

approved

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Last modified May 27 02:31 EDT 2022. Contains 354092 sequences. (Running on oeis4.)