The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A106847 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A106847

a(n) = Sum {k + j*m <= n} (k + j*m), with 0 < k,j,m <= n.
(history; published version)

#30 by N. J. A. Sloane at Sat Jun 22 16:17:47 EDT 2024

STATUS

proposed

approved

#29 by Vaclav Kotesovec at Sat Jun 15 06:48:03 EDT 2024

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editing

proposed

#28 by Vaclav Kotesovec at Sat Jun 15 06:47:51 EDT 2024

FORMULA

a(n) ~ n^3 * (log(n) + 2*gamma - 4/3)/3, where gamma is the Euler-Mascheroni constant A001620. - Vaclav Kotesovec, Jun 15 2024

STATUS

proposed

editing

#27 by Jon E. Schoenfield at Sun Jun 02 08:08:30 EDT 2024

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editing

proposed

#26 by Jon E. Schoenfield at Sun Jun 02 08:07:55 EDT 2024

NAME

a(n) = Sum {k + lj*m <= n} (k + lj*m), with 0 < k,l,j,m <= n.

STATUS

proposed

editing

#25 by Ridouane Oudra at Sun Jun 02 08:05:28 EDT 2024

STATUS

editing

proposed

#24 by Ridouane Oudra at Sun Jun 02 07:57:26 EDT 2024

FORMULA

From Ridouane Oudra, Jun 02 2024: (Start)

a(n) = (1/2)*Sum_{k=1..n} (n^2 + n - k^2 - k)*tau(k);

a(n) = (1/2)*(n^2 + n)*A006218(n) - Sum_{k=1..n} A143272(k);

a(n) = (1/2)*((n + 1)*A143274(n) - A143127(n) - A319085(n)). (End)

CROSSREFS

Cf. A006218, A143272, A143274, A143127, A319085.

STATUS

approved

editing

#23 by Hugo Pfoertner at Thu Apr 04 03:41:46 EDT 2024

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reviewed

approved

#22 by Michel Marcus at Thu Apr 04 03:39:16 EDT 2024

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proposed

reviewed

#21 by Michel Marcus at Thu Apr 04 03:39:11 EDT 2024

STATUS

editing

proposed