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A053018
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Let Do(n)=A006566(n)=n-th dodecahedral number. Consider all integer triples (i,j,k), j >= k>0, with Do(i)=Do(j)+Do(k), ordered by increasing i; sequence gives j values.
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3
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178, 150, 2012, 4840, 7773, 8904, 17403, 22363, 24699, 26200, 21916, 22250, 37022, 39223, 61190, 62899, 102450, 123108, 223132, 269966, 374384, 591930, 554636, 636031, 743699, 892780, 1295888, 1468290, 1395491, 1822152, 1859152, 1957822
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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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Do(179) = 25665020 = 25236484 + 428536 = Do(178) + Do(46);
Do(184) = 27880600 = 15086400 + 12794200 = Do(150) + Do(142).
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MATHEMATICA
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(* This is just a recomputation of j values, given i values. *)
A053017 = Cases[Import["https://oeis.org/A053017/b053017.txt", "Table"], {_, _}][[All, 2]];
do[n_] := n*(3*n - 1)*(3*n - 2)/2;
triples = Reap[Module[{s, i, j, k, n, ijk}, s[i_] := Solve[j >= k > 0 && do[i] == do[j] + do[k], {j, k}, Integers]; For[n = 1, n <= Length[A053017], n++, i = A053017[[n]]; ijk = {i, j, k} /. s[i] // First; Print[ijk]; Sow[ijk]]]][[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 24 2000
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EXTENSIONS
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STATUS
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approved
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