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A054209
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Consider all integer triples (i,j,k), j >= k>0, with i^3=binomial(j+2,3)+binomial(k+2,3), ordered by increasing i; sequence gives j values.
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3
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2, 19, 74, 113, 197, 482, 1162, 1959, 1937, 5644, 6061, 10788, 12772, 17624, 19401, 16503, 29195, 25487, 60881, 63348, 89133, 114519, 140524, 192059, 214754, 262224, 286321
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OFFSET
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0,1
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COMMENTS
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LINKS
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EXAMPLE
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2^3 = 8 = binomial(2+2,3) + binomial(2+2,3).
11^3 = 1331 = binomial(19+2,3) + binomial(3,3).
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MATHEMATICA
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(* This is just a re-computation from A054208 *) A054208 = {2, 11, 45, 65, 109, 280, 644, 1079, 1309, 3180, 3355, 6864, 8284, 9700, 10681, 10856, 16775, 17094, 33506, 35650, 50435}; ijk = Table[ sol = {i, j, k} /. ToRules[ Reduce[ 0 < k <= j && 6*i^3 == j*(j+1)*(j+2) + k*(k+1)*(k+2), {j, k}, Integers]]; Print[sol]; sol, {i, A054208 }]; A054209 = ijk[[All, 2]] (* Jean-François Alcover, Sep 11 2012 *)
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CROSSREFS
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KEYWORD
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nonn,nice,more
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AUTHOR
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Klaus Strassburger (strass(AT)ddfi.uni-duesseldorf.de), Jan 31 2000
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EXTENSIONS
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STATUS
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approved
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