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 A265377 Sums of two or more consecutive positive cubes. 3
 9, 35, 36, 91, 99, 100, 189, 216, 224, 225, 341, 405, 432, 440, 441, 559, 684, 748, 775, 783, 784, 855, 1071, 1196, 1241, 1260, 1287, 1295, 1296, 1584, 1729, 1800, 1925, 1989, 2016, 2024, 2025, 2241, 2331, 2584, 2800, 2925, 2989, 3016, 3024, 3025, 3059, 3060 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS All numbers of the form A000537(b) - A000537(a) for 0 <= a <= b-2. A217843 minus (A000578 minus A131643). n is in the sequence iff n = s*t where (s+t)/2 = A000217(u) and (s-t)/2 = A000217(v) with u-v >= 2. If a(k(n)) = A000537(n+1), k(n) >= A000217(n) for n > 0. - Altug Alkan, Dec 07 2015 See A062682 for sums of two or more consecutive positive cubes in more than one way. - Reinhard Zumkeller, Dec 16 2015 LINKS Robert Israel, Table of n, a(n) for n = 1..10000 EXAMPLE a(1) = 1^3 + 2^3 = 9. a(2) = 2^3 + 3^3 = 35. a(3) = 1^3 + 2^3 + 3^3 = 36. MAPLE amin:= proc(b, N) local r; r:= b^2*(b+1)^2 - 4*N; if r > 0 then iroot(r, 4) else 1 fi end proc: A265377:= proc(N) # to get all terms <= N local a, b; sort(convert(select(`<=`, {seq(seq(b^2*(b+1)^2/4 - a^2*(a-1)^2/4, a = amin(b, N) .. b-1), b=2..1+iroot(floor(N/2), 3))}, N), list)) end proc: A265377(10000); MATHEMATICA With[{nn=12}, Select[Sort[Flatten[Table[Total/@Partition[Range[nn]^3, n, 1], {n, 2, nn}]]], #<=((nn(nn+1))/2)^3&]] (* Harvey P. Dale, Dec 25 2015 *) PROG (Haskell) import Data.Set (singleton, deleteFindMin, insert, Set) a265377 n = a265377_list !! (n-1) a265377_list = f (singleton (1 + 2^3, (1, 2))) (-1) where f s z = if y /= z then y : f s'' y else f s'' y where s'' = (insert (y', (i, j')) \$ insert (y' - i ^ 3 , (i + 1, j')) s') y' = y + j' ^ 3; j' = j + 1 ((y, (i, j)), s') = deleteFindMin s -- Reinhard Zumkeller, Dec 17 2015 CROSSREFS Subset of A217843. Cf. A000217, A000537, A000578, A131643. Cf. A062682 (subsequence). Sequence in context: A067960 A119757 A003865 * A187554 A338010 A267702 Adjacent sequences: A265374 A265375 A265376 * A265378 A265379 A265380 KEYWORD nonn AUTHOR Robert Israel, Dec 07 2015 STATUS approved

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Last modified August 4 16:27 EDT 2024. Contains 374923 sequences. (Running on oeis4.)