The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A338969 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A338969

a(n) is the sum of the lengths of all the segments used to draw a rectangle of height partition(n) and width n divided into partition(n) rectangles of unit height, in turn, divided into rectangles of unit height and lengths corresponding to the parts of the partitions of n.
(history; published version)

#42 by Andrey Zabolotskiy at Sat Nov 13 04:45:02 EST 2021

STATUS

editing

approved

#41 by Andrey Zabolotskiy at Sat Nov 13 04:44:58 EST 2021

MATHEMATICA

a[n_]:=(n+1)PartitionsP[n]+n+Sum[DivisorSigma[0, m] PartitionsP[n-m], {m, n}]; Table[a[n], {n, 40}]]

PROG

a[n_]:=(n+1)PartitionsP[n]+n+Sum[DivisorSigma[0, m] PartitionsP[n-m], {m, n}]; Table[a[n], {n, 40}]]

STATUS

approved

editing

#40 by N. J. A. Sloane at Fri Jan 01 11:56:05 EST 2021

STATUS

proposed

approved

#39 by Hugo Pfoertner at Mon Dec 28 05:43:18 EST 2020

STATUS

editing

proposed

Discussion

Mon Dec 28

06:47

Stefano Spezia: Thanks Hugo. Then I do not upload the colored illustration

#38 by Hugo Pfoertner at Mon Dec 28 05:42:30 EST 2020

EXAMPLE

Illustrations for n = 1..6: _ _ _ _ _ _

_ _ _ _ _ _

#37 by Hugo Pfoertner at Mon Dec 28 05:40:37 EST 2020

EXAMPLE

Illustrations for n = 1..6: _ _ _ _ _ _

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|_ _ _ _| |_ _ _ _ _| |_ _ _ _ _ _|

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STATUS

proposed

editing

#36 by Stefano Spezia at Wed Dec 23 09:14:19 EST 2020

STATUS

editing

proposed

Discussion

Sun Dec 27

23:02

Sean A. Irvine: I like the colour pictures, perhaps add a link to those as well?

Mon Dec 28

05:38

Hugo Pfoertner: The ASCII art becomes better readable if the dots are replaced by spaces. The color picture does not add any information.

#35 by Stefano Spezia at Wed Dec 23 09:06:26 EST 2020

EXAMPLE

_ _._ _._._

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_ _._ _._._

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Discussion

Wed Dec 23

09:14

Stefano Spezia: If you think that the colored illustrations at this link https://drive.google.com/file/d/17WKvITGwY5FCHoL3f08coZaMCvM4tIBj/view?usp=sharing are better, I will delete the actual EXAMPLE

#34 by Stefano Spezia at Wed Dec 23 09:04:59 EST 2020

EXAMPLE

_ _._ _._._

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a(1) = 4 a(2) = 11 a(3) = 21

#33 by Stefano Spezia at Wed Dec 23 09:02:04 EST 2020

EXAMPLE

_ _._ _._._

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_ _._ _._._

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a(1) = 4 a(2) = 11 a(3) = 21