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A165893 Numbers n with property that n(n+2)(n+4) is a triangular number. 2
0, 1, 3, 11, 30, 40, 122, 130, 1972 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
COMMENTS
Abscissas of integral points on the elliptic curve: m^2 = 8*n^3 + 48*n^2 + 64*n + 1.
LINKS
MATHEMATICA
TNQ[n_]:=IntegerQ[Sqrt[1+8n]]; Select[Range[7500], TNQ[ #(#+2)(#+4)]&]
CROSSREFS
Cf. A001219 Triangular numbers of form a(a+1)(a+2), A165892 Triangular numbers of form a(a+2)(a+4).
Sequence in context: A179234 A338051 A009183 * A106397 A295144 A167375
KEYWORD
nonn,fini,full
AUTHOR
Zak Seidov, Sep 29 2009
EXTENSIONS
fini, full keywords from Max Alekseyev, Oct 01 2009
Initial 0 added by Zak Seidov, Oct 04 2009 at the suggestion of Alexander R. Povolotsky.
STATUS
approved

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Last modified July 20 09:30 EDT 2024. Contains 374445 sequences. (Running on oeis4.)