The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A133454

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A133454

Chain of 6 highly composite numbers generated when subject to the recurrence relation tau(a(n+1)) = a(n), with a(0)=3, where tau(n) is the number-of-divisors function A000005(n).
(history; published version)

#13 by R. J. Mathar at Sun Jun 20 08:30:41 EDT 2021

STATUS

editing

approved

#12 by R. J. Mathar at Sun Jun 20 08:30:31 EDT 2021

COMMENTS

We omit the seed a(0) from the sequence and keep the offset at 1, because 3 is not highly composite. - R. J. Mathar, Jun 20 2021

CROSSREFS

Cf. A009287. [R. J. Mathar, Jan 26 2010]

A finite subsequence of A009287.

STATUS

approved

editing

#11 by Joerg Arndt at Wed Nov 29 03:35:11 EST 2017

STATUS

proposed

approved

#10 by Jon E. Schoenfield at Wed Nov 29 02:25:36 EST 2017

STATUS

editing

proposed

#9 by Jon E. Schoenfield at Wed Nov 29 02:25:33 EST 2017

NAME

Chain of 6 highly composite numbers generated when subject to the recurrence relation tau(a(n+1)) = a(n), with a(0)=3, where tau(n) is the number-of-divisors function A000005(n).

EXAMPLE

Since 4 is the HCN with 3 divisors, we have tau(4) = 3 and therefore a(1)=4 ; The the HCN with 4 divisors is 6, so that tau(6) = 4 and hence a(2)=6 ; The the HCN with 6 divisors is 12 so that tau(12) = 6, implying a(3)=12, ...

CROSSREFS

Cf. A009287. [From __R. J. Mathar_, Jan 26 2010]

STATUS

approved

editing

#8 by Russ Cox at Sat Mar 31 10:26:06 EDT 2012

AUTHOR

_Lekraj Beedassy (blekraj(AT)yahoo.com), _, Dec 22 2007

Discussion

Sat Mar 31

10:26

OEIS Server: https://oeis.org/edit/global/489

#7 by Russ Cox at Fri Mar 30 17:39:25 EDT 2012

CROSSREFS

Cf. A009287. [From _R. J. Mathar (mathar(AT)strw.leidenuniv.nl), _, Jan 26 2010]

Discussion

Fri Mar 30

17:39

OEIS Server: https://oeis.org/edit/global/190

#6 by R. J. Mathar at Thu Mar 29 07:28:03 EDT 2012

COMMENTS

Duplicate of A009287.

KEYWORD

fini,full,nonn,changed

STATUS

proposed

approved

#5 by R. J. Mathar at Wed Mar 28 14:32:58 EDT 2012

STATUS

editing

proposed

#4 by R. J. Mathar at Wed Mar 28 14:32:53 EDT 2012

COMMENTS

Duplicate of A009287.

STATUS

approved

editing