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A054207
Consider all integer triples (i,j,k), j >= k > 0, with binomial(i+2,3)=j^3+k^3, ordered by increasing i; sequence gives k values.
3
2, 31, 80, 120, 282, 17, 525, 437, 386, 2479, 5253, 3268, 2952, 3875, 8894, 7182, 9457, 16397, 3401, 8629, 1830, 2518, 19976, 37326, 55340, 21182, 98642, 56358, 150673, 17220, 211196, 185129, 223680, 98763, 219284, 138712, 145330, 532762, 676971, 68490, 776927, 405452, 26488
OFFSET
1,1
COMMENTS
The i values are in A054205 and j values in A054206.
LINKS
EXAMPLE
binomial(5+2,3)=35=2^3+3^3; binomial(95+2,3)=147440=49^3+31^3;
MATHEMATICA
lst = {}; Do[ b = Binomial[i + 2, 3]; j = Floor[b^(1/3)]; lmt = Ceiling[j/2]; While[ k = (b - j^3)^(1/3); j > lmt && !IntegerQ[k], j-- ]; If[j != lmt, Print[{i, j, k}]; AppendTo[lst, {i, j, k}]], {i, 2, 30000}]; Last /@ lst (* Robert G. Wilson v, Jan 15 2007 *)
CROSSREFS
KEYWORD
nice,nonn
AUTHOR
Klaus Strassburger (strass(AT)ddfi.uni-duesseldorf.de), Jan 28 2000
EXTENSIONS
More terms from Martin Fuller, Nov 27 2006
Offset corrected by N. J. A. Sloane, Jan 14 2009
a(30)-a(36) from Jon E. Schoenfield, Jan 14 2009
a(37)-a(43) from Jon E. Schoenfield, Aug 30 2013
STATUS
approved