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Revision History for A317305

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A317305

Sum of divisors of the n-th number whose divisors increase by a factor of 2 or less.
(history; published version)

#46 by Michael De Vlieger at Mon Oct 16 22:25:21 EDT 2023

STATUS

proposed

approved

#45 by Peter Munn at Mon Oct 16 20:26:39 EDT 2023

STATUS

editing

proposed

#44 by Peter Munn at Mon Oct 16 20:22:30 EDT 2023

FORMULA

a(n) = A000203(A238443(n)).

CROSSREFS

Cf. A317307 is a subsequence.

Cf. A174973 same as A238443.

STATUS

approved

editing

Discussion

Mon Oct 16

20:25

Peter Munn: A238443 is a dead duplicate.

#43 by N. J. A. Sloane at Thu Mar 09 06:24:15 EST 2023

STATUS

proposed

approved

#42 by Omar E. Pol at Wed Mar 08 06:13:39 EST 2023

STATUS

editing

proposed

#41 by Omar E. Pol at Wed Mar 08 05:31:13 EST 2023

FORMULA

a(n) = A000203(A174973(n)) = A000203(A238443(n)).

a(n) = A000203(A238443(n)).

#40 by Omar E. Pol at Wed Mar 08 05:28:52 EST 2023

NAME

Sum of divisors of the numbers n-th number whose divisors increase by a factor of 2 or less.

COMMENTS

Also sum of divisors of consider the numbers n-th number k whose with the property that the symmetric representation of sigma(k) has only one part. a(n) is the area of the diagram (see the example). For more information see A237593 and its related sequences.

EXAMPLE

Illustration of initial terms (n = 1..13):

The length of the largest Dyck path of the n-th set of regions of the diagram equals A047836(n) and the semilength equals A174973(n).

The semilength equals A174973(n).

a(n) is the area of the n-th diagram.

STATUS

proposed

editing

Discussion

Wed Mar 08

05:30

Omar E. Pol: Improvements. Minor edits.

#39 by Omar E. Pol at Tue Mar 07 10:34:31 EST 2023

STATUS

editing

proposed

#38 by Omar E. Pol at Mon Mar 06 15:50:25 EST 2023

CROSSREFS

Cf. A000203, A047836, A196020, A236104, A235791, A237048, A237591, A237593, A237270, A237271, A239660, A239931, A239932, A239933, A239934, A244050, A245092, A262626, A361208.

#37 by Omar E. Pol at Mon Mar 06 15:49:04 EST 2023

LINKS

<a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>

STATUS

approved

editing