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A054234
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Consider all integer triples (i,j,k), j,k>0, with i^3=j^3+binomial(k+2,3), ordered by increasing i; sequence gives i values.
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3
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4, 11, 75, 108, 120, 427, 1309, 1583, 1753, 2490, 2712, 2764, 2822, 3678, 4502, 4569, 4595, 7526, 9667, 13723, 14279, 18869, 36367, 37964, 42669, 43738, 46820, 52849, 57666, 59922, 71592, 80480, 85480, 96862, 108383, 121828, 122426, 131318, 131398, 155760, 167021
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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4^3=64=2^3+binomial(6+2,3); 11^3=1331=1^3+binomial(19+2,3)
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MATHEMATICA
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nmax = 21;
ijk[0] = {1, 1, 0};
ijk[n_] := ijk[n] = Module[{i, j, k, r}, For[i = ijk[n-1][[1]]+1, True, i++, r = Reduce[0<j<i && k>0 && i^3 == j^3 + Binomial[k+2, 3], {j, k}, Integers]; If[r =!= False, Return[{i, j, k} /. ToRules[r]]]]];
triples = Reap[For[n=1, n<=nmax, n++, Print[ijk[n]]; Sow[ijk[n]]]][[2, 1]];
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CROSSREFS
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KEYWORD
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nice,nonn
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AUTHOR
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Klaus Strassburger (strass(AT)ddfi.uni-duesseldorf.de), Feb 07 2000
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EXTENSIONS
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STATUS
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approved
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