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 A240698 Partial sums of divisors of n, cf. A027750. 11
 1, 1, 3, 1, 4, 1, 3, 7, 1, 6, 1, 3, 6, 12, 1, 8, 1, 3, 7, 15, 1, 4, 13, 1, 3, 8, 18, 1, 12, 1, 3, 6, 10, 16, 28, 1, 14, 1, 3, 10, 24, 1, 4, 9, 24, 1, 3, 7, 15, 31, 1, 18, 1, 3, 6, 12, 21, 39, 1, 20, 1, 3, 7, 12, 22, 42, 1, 4, 11, 32, 1, 3, 14, 36, 1, 24, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS T(n,1) = 1; T(n,A000005(n)) = A000203(n); T(n,A000005(n)-1) = A001065(n), n > 1. Triangle read by rows in which row n lists the partial sums of divisors of n. - Omar E. Pol, Apr 12 2014 LINKS Reinhard Zumkeller, Rows n = 1..1000 of table, flattened FORMULA T(n,1) = 1, T(n,k) = T(n,k-1) + A027750(n,k), 1 < k <= n. EXAMPLE .    n |  n-th row of A240698   |  n-th row of A027750 .  ----+------------------------+--------------------- .    1 |  1                     |  1 .    2 |  1, 3                  |  1, 2 .    3 |  1, 4                  |  1, 3 .    4 |  1, 3, 7               |  1, 2, 4 .    5 |  1, 6                  |  1, 5 .    6 |  1, 3, 6, 12           |  1, 2, 3, 6 .    7 |  1, 8                  |  1, 7 .    8 |  1, 3, 7, 15           |  1, 2, 4, 8 .    9 |  1, 4, 13              |  1, 3, 9 .   10 |  1, 3, 8, 18           |  1, 2, 5, 10 .   11 |  1, 12                 |  1, 11 .   12 |  1, 3, 6, 10, 16, 28   |  1, 2, 3, 4, 6, 12 .   13 |  1, 14                 |  1, 13 . MATHEMATICA Table[Accumulate[Divisors[n]], {n, 30}]//Flatten (* Harvey P. Dale, Dec 30 2019 *) PROG (Haskell) a240698 n k = a240698_tabf !! (n-1) !! (k-1) a240698_row n = a240698_tabf !! (n-1) a240698_tabf = map (scanl1 (+)) a027750_tabf CROSSREFS Cf. A000005 (row lengths), A240694. Cf. A064510, A194472. Sequence in context: A278536 A143825 A290478 * A010602 A120731 A294098 Adjacent sequences:  A240695 A240696 A240697 * A240699 A240700 A240701 KEYWORD nonn,tabf AUTHOR Reinhard Zumkeller, Apr 10 2014 STATUS approved

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Last modified June 23 16:43 EDT 2021. Contains 345402 sequences. (Running on oeis4.)