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A265845 Numbers that are sums of consecutive (positive) cubes in more than one way. 6
216, 8000, 33075, 64000, 89559, 105525, 164800, 188784, 189189, 216000, 343000, 353241, 443456, 608391, 1271600, 2370816, 3132116, 3132675, 3184236, 5821200, 5832000, 9018000, 9769375, 11437525, 20793591, 22153600, 24359616, 28685440, 35937000, 47651373 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

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

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..1000

EXAMPLE

a(1) = 216 = 6^3 = 3^3 + 4^3 + 5^3;

a(2) = 8000 = 20^3 = 11^3 + 12^3 + 13^3 + 14^3;

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.

PROG

(Haskell)

import Data.Set (singleton, deleteFindMin, insert, Set)

a265845 n = a265845_list !! (n-1)

a265845_list = f (singleton (1, (1, 1))) 0 0 where

   f s z z' = if y == z && z' /= z then y : f s'' y z else f s'' y z

              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

CROSSREFS

Subsequence of A217843; subsequences: A000578, A005898, A027602, A027603, A062682.

Supersequence of A131643.

Sequence in context: A017595 A232835 A223272 * A131643 A269139 A231319

Adjacent sequences:  A265842 A265843 A265844 * A265846 A265847 A265848

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Dec 16 2015

STATUS

approved

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Last modified July 23 04:27 EDT 2019. Contains 325234 sequences. (Running on oeis4.)