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A165893
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Numbers n with property that n(n+2)(n+4) is a triangular number.
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2
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OFFSET
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1,3
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COMMENTS
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Abscissas of integral points on the elliptic curve: m^2 = 8*n^3 + 48*n^2 + 64*n + 1.
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LINKS
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MATHEMATICA
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TNQ[n_]:=IntegerQ[Sqrt[1+8n]]; Select[Range[7500], TNQ[ #(#+2)(#+4)]&]
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CROSSREFS
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Cf. A001219 Triangular numbers of form a(a+1)(a+2), A165892 Triangular numbers of form a(a+2)(a+4).
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KEYWORD
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nonn,fini,full
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AUTHOR
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EXTENSIONS
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Initial 0 added by Zak Seidov, Oct 04 2009 at the suggestion of Alexander R. Povolotsky.
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STATUS
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approved
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