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Revision History for A322661

(Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
Showing entries 1-10 | older changes

A322661

Number of graphs with loops spanning n labeled vertices.
(history; published version)

#14 by OEIS Server at Sat Jan 06 13:10:24 EST 2024

LINKS

Andrew Howroyd, <a href="/A322661/b322661_1.txt">Table of n, a(n) for n = 0..50</a>

#13 by Peter Luschny at Sat Jan 06 13:10:24 EST 2024

STATUS

reviewed

approved

Discussion

Sat Jan 06

13:10

OEIS Server: Installed first b-file as b322661.txt.

#12 by Stefano Spezia at Sat Jan 06 13:08:49 EST 2024

STATUS

proposed

reviewed

#11 by Andrew Howroyd at Sat Jan 06 12:57:55 EST 2024

STATUS

editing

proposed

#10 by Andrew Howroyd at Sat Jan 06 12:57:45 EST 2024

LINKS

Andrew Howroyd, <a href="/A322661/b322661_1.txt">Table of n, a(n) for n = 0..50</a>

PROG

(PARI) a(n) = sum(k=0, n, (-1)^(n-k)*binomial(n, k)*2^binomial(k+1, 2)) \\ Andrew Howroyd, Jan 06 2024

STATUS

approved

editing

#9 by R. J. Mathar at Mon Nov 20 12:52:43 EST 2023

STATUS

editing

approved

#8 by R. J. Mathar at Mon Nov 20 11:55:31 EST 2023

CROSSREFS

Cf. A000666, A006125, A006129, (loops not allowed), A054921, A062740, A116539, A320461, A322635, A048291 (for directed edgs).

#7 by R. J. Mathar at Mon Nov 20 11:51:54 EST 2023

CROSSREFS

Cf. A000666, A006125, A006129, A054921, A062740, A116539, A320461, A322635, A048291 (for directed edgs).

STATUS

approved

editing

#6 by Susanna Cuyler at Sun Dec 23 11:21:54 EST 2018

STATUS

proposed

approved

#5 by Gus Wiseman at Sun Dec 23 00:00:46 EST 2018

STATUS

editing

proposed