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Numbers that are the sum of 2 cubes > 1.
2

%I #12 Feb 09 2018 15:48:24

%S 16,35,54,72,91,128,133,152,189,224,243,250,280,341,351,370,407,432,

%T 468,520,539,559,576,637,686,728,737,756,793,854,855,945,1008,1024,

%U 1027,1064,1072,1125,1216,1241,1339,1343,1358,1395,1456,1458,1512,1547,1674,1729,1736,1755,1792,1843,1853,1944,2000,2060

%N Numbers that are the sum of 2 cubes > 1.

%H Robert Israel, <a href="/A294073/b294073.txt">Table of n, a(n) for n = 1..10000</a>

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

%e 133 is in the sequence because 133 = 2^3 + 5^3.

%p N:= 3000: # to get all terms <= N

%p M := floor(N^(1/3)):

%p sort(convert(select(`<=`, {seq(seq(i^3+j^3, j = 2 .. i), i = 2 .. M)}, N), list)) # _Robert Israel_, Feb 08 2018

%t nmax = 2060; f[x_] := Sum[x^k^3, {k, 2, 14}]^2; Exponent[#, x] & /@ List @@ Normal[Series[f[x], {x, 0, nmax}]]

%Y Cf. A000578, A003325, A004999, A024670, A085989, A086119.

%K nonn

%O 1,1

%A _Ilya Gutkovskiy_, Feb 07 2018