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 A113958 Triangular numbers that can be written as sum of two positive cubes. 4

%I

%S 28,91,351,2926,8001,46971,58653,93528,97461,141778,300700,365085,

%T 382375,398278,874503,1295245,1669878,3425653,4117015,7517503,7657741,

%U 7771653,9415630,9598771

%N Triangular numbers that can be written as sum of two positive cubes.

%C Intersection of A003325 and A000217.

%H Donovan Johnson, <a href="/A113958/b113958.txt">Table of n, a(n) for n = 1..5122</a>

%H <a href="/index/Su#ssq">Index entries for sequences related to sums of cubes</a>

%e 91 = 13*(13+1)/2 = 4^3 + 3^3, therefore 91 is a term.

%t Sort[Select[Total/@Subsets[Range[300]^3,{2}],OddQ[Sqrt[8#+1]]&]] (* _Harvey P. Dale_, Oct 10 2014 *)

%Y Cf. A119977, A003108, A000578.

%K nonn

%O 1,1

%A _Reinhard Zumkeller_, Jun 03 2006

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Last modified October 20 20:24 EDT 2019. Contains 328273 sequences. (Running on oeis4.)