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Revision History for A227096

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

A227096

Self-convolution of A013999.
(history; published version)

#17 by Peter Luschny at Tue Feb 14 06:30:36 EST 2023

STATUS

reviewed

approved

#16 by Michel Marcus at Tue Feb 14 05:57:51 EST 2023

STATUS

proposed

reviewed

#15 by Jean-François Alcover at Tue Feb 14 05:25:24 EST 2023

STATUS

editing

proposed

#14 by Jean-François Alcover at Tue Feb 14 05:25:13 EST 2023

MATHEMATICA

f[n_] := Sum[Binomial[n-k+1, k] (-1)^k (n-k+1)!, {k, 0, Quotient[n+1, 2]}];

a[n_] := Sum[f[k] f[n-k], {k, 0, n}];

Table[a[n], {n, 0, 30}] (* Jean-François Alcover, Feb 14 2023 *)

STATUS

approved

editing

#13 by Alois P. Heinz at Mon Jul 08 15:02:48 EDT 2013

STATUS

editing

approved

#12 by Alois P. Heinz at Mon Jul 08 15:02:41 EDT 2013

LINKS

Alois P. Heinz, <a href="/A227096/b227096.txt">Table of n, a(n) for n = 0..200</a>

STATUS

proposed

editing

#11 by Vaclav Kotesovec at Mon Jul 08 14:49:10 EDT 2013

STATUS

editing

proposed

#10 by Vaclav Kotesovec at Mon Jul 08 14:49:03 EDT 2013

FORMULA

a(n) ~ 2*n*n!/exp(1). - Vaclav Kotesovec, Jul 08 2013

STATUS

approved

editing

#9 by Alois P. Heinz at Mon Jul 01 17:36:21 EDT 2013

STATUS

editing

approved

#8 by Alois P. Heinz at Mon Jul 01 17:35:51 EDT 2013

DATA

1, 2, 5, 20, 104, 632, 4396, 34680, 307236, 3026472, 32849364, 389704800, 5017492320, 69678231552, 1038078389376, 16513758904320, 279354776803200, 5007072973075200, 94783054774919040, 1889504358498754560, 39565281716813111040, 868194780280625779200

STATUS

proposed

editing