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%I #26 Feb 05 2023 09:24:10
%S 0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,
%T 0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,
%U 0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
%N a(n) is the number of partitions of n into 2 distinct positive cubes.
%C In other words, number of solutions to the equation n = x^3 + y^3 with x > y > 0. The first value > 1 is a(1729) = 2. - _Antti Karttunen_, Aug 29 2017
%H Antti Karttunen, <a href="/A025468/b025468.txt">Table of n, a(n) for n = 0..100000</a>
%H <a href="/index/Su#ssq">Index entries for sequences related to sums of cubes</a>
%F From _Antti Karttunen_, Aug 28-29 2017: (Start)
%F a(n) = A025465(n) - A025469(n).
%F a(n) <= A025455(n).
%F (End)
%o (Scheme) (define (A025468 n) (let loop ((x (A048766 n)) (s 0)) (let* ((x3 (A000578 x)) (y3 (- n x3))) (if (<= x3 y3) s (loop (- x 1) (+ s (if (and (> y3 0) (= (A000578 (A048766 y3)) y3)) 1 0))))))) ;; _Antti Karttunen_, Aug 28 2017
%Y Cf. A000578, A048766, A025455, A025465, A025469.
%K nonn
%O 0,1730
%A _David W. Wilson_
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