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A127707 Number of commutative rings with 1 containing n elements. 1
1, 1, 1, 4, 1, 1, 1, 10, 4, 1, 1, 4, 1, 1, 1, 37, 1, 4, 1, 4, 1, 1, 1, 10, 4, 1, 11, 4, 1, 1, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

Is this a multiplicative function?

Answer: yes! See the Eric M. Rains link for a proof for the result for all unital rings; restricting to commutative rings does not affect the essence of the proof. - Jianing Song, Feb 02 2020

LINKS

Table of n, a(n) for n=1..31.

C. Noebauer, Home page [Archived copy as of 2008 from web.archive.org]

Eric M. Rains, The number of unital rings with n elements is a multiplicative function of n.

CROSSREFS

Cf. A037289, A037291, A127708.

Sequence in context: A303278 A222639 A184729 * A113196 A037291 A222317

Adjacent sequences:  A127704 A127705 A127706 * A127708 A127709 A127710

KEYWORD

more,nice,nonn,mult

AUTHOR

Hugues Randriam (randriam(AT)enst.fr), Jan 24 2007

EXTENSIONS

Keyword 'mult' added by Jianing Song, Feb 02 2020

STATUS

approved

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Last modified September 18 07:39 EDT 2020. Contains 337166 sequences. (Running on oeis4.)