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%I #9 Dec 30 2012 02:43:29
%S 730,737,756,793,854,945,1072,1241,2060,2457,2926,3473,4825,5642,6561,
%T 7588,8729,9990,11377,12896,14553,16354,18305,20412,21953,21960,21979,
%U 22016,22077,22168,22295,22464,22681,22952,23283,23680,24149,24696
%N Terms of A024670 that are not in A141805.
%C A024670 gives the sums of cubes of two distinct positive integers. A141805, the complement of A031980, is a subsequence of A024670.
%H Klaus Brockhaus, <a href="/A141806/b141806.txt">Table of n, a(n) for n = 1..2774</a>
%H <a href="/index/Su#ssq">Index to sequences related to sums of squares and sums of cubes</a>
%e 1072 is the sum of two distinct nonzero cubes in exactly one way: 1072 = 7^3 + 9^3. 9 is not in A031980, so 1072 is not the sum of cubes of two distinct earlier terms of A031980 and hence 1072 is in A031980. Therefore 1072 is in not in A141805 and so a term of this sequence.
%e 1729 is the sum of two distinct nonzero cubes in exactly two ways: 1729 = 9^3 + 10^3 = 1^3 + 12^3. 1 and 12 are in A031980, so 1729 is the sum of cubes of two distinct earlier terms of A031980 and hence 1729 is in not A031980. Therefore 1729 is in A141805 and so not a term of this sequence.
%Y Cf. A024670, A141805, A031980 (smallest number not occurring earlier and not the sum of cubes of two distinct earlier terms).
%K nonn
%O 1,1
%A _Klaus Brockhaus_, Jul 16 2008
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