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Revision History for A111521 (Bold, blue-underlined text is an addition; faded, red-underlined text is a deletion.)

Showing entries 1-10 | older changes
Sequence is {a(3,n)}, where a(m,n) is defined at sequence A111518.
(history; published version)
#13 by Susanna Cuyler at Mon Sep 21 08:37:48 EDT 2020
STATUS

proposed

approved

#12 by Jean-François Alcover at Mon Sep 21 03:40:19 EDT 2020
STATUS

editing

proposed

#11 by Jean-François Alcover at Mon Sep 21 03:40:16 EDT 2020
MATHEMATICA

nmax = 26;

a[_, 0] = 1;

a[m_ /; m > 0, n_ /; n > 0] := a[m, n] = a[m - 1, n] + a[m, n - 1];

sol = Solve[Table[a[n + 1, n + 1] == a[0, n], {n, 0, nmax}], Table[a[0, n], {n, 1, nmax + 1}], Integers] // First;

Do[a[m, n] = a[m, n] /. sol, {m, 0, nmax}, {n, 0, nmax}];

Table[a[3, n], {n, 0, nmax}] (* Jean-François Alcover, Sep 21 2020 *)

STATUS

approved

editing

#10 by Jon E. Schoenfield at Sun Aug 09 00:47:09 EDT 2015
STATUS

editing

approved

#9 by Jon E. Schoenfield at Sun Aug 09 00:47:07 EDT 2015
MAPLE

A111521T := proc(nmax) local a, m, n; a := array(0..nmax, 0..nmax) ; for m from 0 to nmax do a[m, 0] := 1 ; od ; for n from 1 to nmax do a[n, n] := a[0, n-1] ; for m from n+1 to nmax do a[m, n] := a[m-1, n]+a[m, n-1] ; od ; for m from n-1 to 0 by -1 do a[m, n] := a[m+1, n]-a[m+1, n-1] ; od ; od ; RETURN(a) ; end: nmax := 50 ; a := A111521T(nmax) ; m := 3 ; for n from 0 to nmax do printf("%d, ", a[m, n]) ; od; - _# _R. J. Mathar_, Sep 26 2006

STATUS

approved

editing

#8 by Charles R Greathouse IV at Wed Apr 09 10:15:51 EDT 2014
AUTHOR

Leroy Quet , Aug 05 2005

Discussion
Wed Apr 09
10:15
OEIS Server: https://oeis.org/edit/global/2152
#7 by N. J. A. Sloane at Wed Feb 05 20:18:14 EST 2014
AUTHOR

_Leroy Quet _ Aug 05 2005

Discussion
Wed Feb 05
20:18
OEIS Server: https://oeis.org/edit/global/2118
#6 by Russ Cox at Fri Mar 30 17:39:07 EDT 2012
MAPLE

A111521T := proc(nmax) local a, m, n; a := array(0..nmax, 0..nmax) ; for m from 0 to nmax do a[m, 0] := 1 ; od ; for n from 1 to nmax do a[n, n] := a[0, n-1] ; for m from n+1 to nmax do a[m, n] := a[m-1, n]+a[m, n-1] ; od ; for m from n-1 to 0 by -1 do a[m, n] := a[m+1, n]-a[m+1, n-1] ; od ; od ; RETURN(a) ; end: nmax := 50 ; a := A111521T(nmax) ; m := 3 ; for n from 0 to nmax do printf("%d, ", a[m, n]) ; od; - _R. J. Mathar (mathar(AT)strw.leidenuniv.nl), _, Sep 26 2006

EXTENSIONS

More terms from _R. J. Mathar (mathar(AT)strw.leidenuniv.nl), _, Sep 26 2006

Discussion
Fri Mar 30
17:39
OEIS Server: https://oeis.org/edit/global/190
#5 by N. J. A. Sloane at Sat Oct 02 03:00:00 EDT 2010
LINKS

Leroy Quet, <a href="http://www.prism-of-spirals.net/">Home Page</a> (listed in lieu of email address)

KEYWORD

easy,sign,new

#4 by N. J. A. Sloane at Fri Jan 09 03:00:00 EST 2009
LINKS

Leroy Quet, <a href="http://www.prism-of-spirals.net/">Home Page</a> (listed in lieu of email address)

KEYWORD

easy,sign,new

AUTHOR

Leroy Quet (qq-quet(AT)mindspring.com), Aug 05 2005