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A051388 Numbers whose 4th power can be expressed as the sum of two positive cubes in more than one way. 2
1729, 2457, 4104, 4914, 4977, 8001, 8216, 10773, 13832, 15561, 16263, 19656, 20683, 32832, 39312, 39816, 40033, 46683, 64008, 64232, 65728, 66339, 80236, 86184, 110656, 110808, 124336, 124488, 127062, 130104, 132678, 132867, 134379, 149389, 157248, 165464, 166887, 171288 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Chai Wah Wu, Table of n, a(n) for n = 1..358

EXAMPLE

1729^4 = 1729^3 + 20748^3 = 15561^3 + 17290^3.

PROG

(PARI) for(i=1, 10^5, x=i^4; c=0; for(j=1, floor(sqrtn(x/2, 3)), if(ispower(x-j^3, 3), c++)); if(c>1, print(i" "c))) \\ Donovan Johnson, Aug 03 2009

CROSSREFS

Cf. A051386, A051387.

Cf. A226777, A226950.

Sequence in context: A288153 A154717 A306478 * A033181 A300949 A198775

Adjacent sequences:  A051385 A051386 A051387 * A051389 A051390 A051391

KEYWORD

nonn

AUTHOR

Jud McCranie

EXTENSIONS

More terms from John W. Layman, Feb 24 2003

a(18)-a(24) from Donovan Johnson, Aug 03 2009

a(25)-a(38) from Donovan Johnson, Dec 03 2010

STATUS

approved

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Last modified September 17 06:41 EDT 2019. Contains 327119 sequences. (Running on oeis4.)