|
| |
|
|
A051388
|
|
Numbers whose 4th power can be expressed as the sum of two positive cubes in more than one way.
|
|
0
| |
|
|
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; internal format)
|
|
|
|
OFFSET
| 1,1
|
|
|
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))) [From Donovan Johnson (donovan.johnson(AT)yahoo.com), Aug 03 2009]
|
|
|
CROSSREFS
| Cf. A051386, A051387.
Sequence in context: A112140 A044883 A154717 * A033181 A198775 A154729
Adjacent sequences: A051385 A051386 A051387 * A051389 A051390 A051391
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Jud McCranie (JudMcCranie(AT)ugaalum.uga.edu)
|
|
|
EXTENSIONS
| More terms from John W. Layman (layman(AT)math.vt.edu), Feb 24 2003
a(18)-a(24) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Aug 03 2009
a(25)-a(38) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Dec 03 2010
|
| |
|
|
