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A265845 Numbers that are sums of consecutive (positive) cubes in more than one way.

%I A265845 #8 Jan 11 2016 03:12:25
%S A265845 216,8000,33075,64000,89559,105525,164800,188784,189189,216000,343000,
%T A265845 353241,443456,608391,1271600,2370816,3132116,3132675,3184236,5821200,
%U A265845 5832000,9018000,9769375,11437525,20793591,22153600,24359616,28685440,35937000,47651373
%N A265845 Numbers that are sums of consecutive (positive) cubes in more than one way.
%C A265845 A131643 (cubes that are also sums of three or more consecutive positive cubes) is a sparse subsequence: only 17 of its terms appear in the first 1000 terms of A265845. - _Jonathan Sondow_, Jan 10 2016
%H A265845 Reinhard Zumkeller, <a href="/A265845/b265845.txt">Table of n, a(n) for n = 1..1000</a>
%e A265845 a(1) = 216 = 6^3 = 3^3 + 4^3 + 5^3;
%e A265845 a(2) = 8000 = 20^3 = 11^3 + 12^3 + 13^3 + 14^3;
%e A265845 a(3) = 33075 = 11^3 + 12^3 + 13^3 + 14^3 + 15^3 + 16^3 + 17^3 + 18^3 + 19^3 = 15^3 + 16^3 + 17^3 + 18^3 + 19^3 + 20^3.
%o A265845 (Haskell)
%o A265845 import Data.Set (singleton, deleteFindMin, insert, Set)
%o A265845 a265845 n = a265845_list !! (n-1)
%o A265845 a265845_list = f (singleton (1, (1, 1))) 0 0 where
%o A265845    f s z z' = if y == z && z' /= z then y : f s'' y z else f s'' y z
%o A265845               where s'' = (insert (y', (i, j')) $
%o A265845                            insert (y' - i ^ 3 , (i + 1, j')) s')
%o A265845                     y' = y + j' ^ 3; j' = j + 1
%o A265845                     ((y, (i, j)), s') = deleteFindMin s
%Y A265845 Subsequence of A217843; subsequences: A000578, A005898, A027602, A027603, A062682.
%Y A265845 Supersequence of A131643.
%K A265845 nonn
%O A265845 1,1
%A A265845 _Reinhard Zumkeller_, Dec 16 2015