The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A305622

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A305622

Triangle read by rows: T(n,k) is the number of chiral pairs of rows of n colors with exactly k different colors.
(history; published version)

#25 by N. J. A. Sloane at Sat Sep 14 12:20:24 EDT 2019

STATUS

proposed

approved

#24 by Andrew Howroyd at Sat Sep 14 11:45:43 EDT 2019

STATUS

editing

proposed

#23 by Andrew Howroyd at Sat Sep 14 11:45:36 EDT 2019

LINKS

Andrew Howroyd, <a href="/A305622/b305622.txt">Table of n, a(n) for n = 1..1275</a> (first 50 rows)

STATUS

reviewed

editing

#22 by Michel Marcus at Sat Sep 14 11:39:17 EDT 2019

STATUS

proposed

reviewed

Discussion

Sat Sep 14

11:39

Michel Marcus: for b-file, maybe add how many rows

#21 by Andrew Howroyd at Sat Sep 14 11:24:20 EDT 2019

STATUS

editing

proposed

#20 by Andrew Howroyd at Fri Sep 13 13:38:20 EDT 2019

LINKS

Andrew Howroyd, <a href="/A305622/b305622.txt">Table of n, a(n) for n = 1..1275</a>

FORMULA

T(n, k) = Sum_{i=0..k} (-1)^(k-i)*binomial(k,i)*A293500(n, i). - Andrew Howroyd, Sep 13 2019

EXAMPLE

0;

0, 1;

0, 2, 3;

0, 6, 18, 12;

0, 12, 72, 120, 60;

0, 28, 267, 780, 900, 360;

0, 56, 885, 4188, 8400, 7560, 2520;

0, 120, 2880, 20400, 63000, 95760, 70560, 20160;

0, 240, 9000, 93120, 417000, 952560, 1164240, 725760, 181440;

...

CROSSREFS

Row sums are A327091.

Cf. A008277, A019538, A293500, A305621.

STATUS

approved

editing

#19 by Bruno Berselli at Thu Sep 27 05:24:47 EDT 2018

STATUS

proposed

approved

#18 by Michel Marcus at Thu Sep 27 04:17:47 EDT 2018

STATUS

editing

proposed

#17 by Michel Marcus at Thu Sep 27 04:17:45 EDT 2018

CROSSREFS

Cf. A008277, A019538, A305621.

STATUS

proposed

editing

#16 by Muniru A Asiru at Thu Sep 27 04:15:59 EDT 2018

STATUS

editing

proposed