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A152967 Partial sums of A152770. 1
0, 0, 0, 1, 1, 4, 4, 8, 10, 15, 15, 26, 26, 33, 39, 50, 50, 66, 66, 83, 91, 102, 102, 131, 135, 148, 158, 181, 181, 216, 216, 242, 254, 271, 281, 328, 328, 347, 361, 404, 404, 451, 451, 486, 514, 537, 537, 604, 610, 648, 666, 707, 707, 766, 780, 837, 857, 886, 886, 983, 983 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,6

LINKS

B. D. Swan, Table of n, a(n) for n=1..10000

FORMULA

a(n) = Sum_{i=1..n} (i-1)*floor((n-i)/i). - Wesley Ivan Hurt, Sep 13 2017

MATHEMATICA

Accumulate[Array[DivisorSigma[1, #]-DivisorSigma[0, #]-#+1&, 70]] (* Harvey P. Dale, Dec 27 2011 *)

CROSSREFS

Cf. A152770.

Sequence in context: A180854 A014687 A172022 * A301705 A004024 A292276

Adjacent sequences:  A152964 A152965 A152966 * A152968 A152969 A152970

KEYWORD

easy,nonn

AUTHOR

Omar E. Pol, Dec 22 2008

STATUS

approved

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Last modified January 18 20:57 EST 2019. Contains 319282 sequences. (Running on oeis4.)