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Triangle T(n,m) read by rows: m! if m <= floor(n/2), and (n-m)! otherwise.
(history; published version)
#6 by N. J. A. Sloane at Sat Jan 21 10:48:04 EST 2017
STATUS

editing

approved

#5 by N. J. A. Sloane at Sat Jan 21 10:48:01 EST 2017
NAME

Triangle T(n,m) read by rows: m! if m <= floor(n/2), and (n-m)! elseotherwise.

STATUS

approved

editing

#4 by Charles R Greathouse IV at Fri Oct 12 14:54:50 EDT 2012
AUTHOR

_Roger L. Bagula _ and _Gary W. Adamson (rlbagulatftn(AT)yahoo.com), _, May 30 2008

Discussion
Fri Oct 12
14:54
OEIS Server: https://oeis.org/edit/global/1840
#3 by N. J. A. Sloane at Tue Jun 01 03:00:00 EDT 2010
NAME

Triangular sequence from a symmetrical factorial function: f(n,m)=If[m (nonascii character here) Floor[n/2], m!, (n - m)! ].

Triangle T(n,m) read by rows: m! if m <= floor(n/2), and (n-m)! else.

DATA

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 2, 1, 1, 1, 1, 2, 6, 2, 1, 1, 1, 1, 2, 6, 6, 2, 1, 1, 1, 1, 2, 6, 24, 6, 2, 1, 1, 1, 1, 2, 6, 24, 24, 6, 2, 1, 1, 1, 1, 2, 6, 24, 120, 24, 6, 2, 1, 1, 1, 1, 2, 6, 24, 120, 120, 24, 6, 2, 1, 1, 1, 1, 2, 6, 24, 120, 720, 120, 24, 6, 2, 1, 1, 1, 1, 2, 6, 24

OFFSET

1,0,13

COMMENTS

Row sums: 1, 2, 3, 4, 6, 8, 14, 20, 44, 68, 188,... which is

{1, 2, 3, 4, 6, 8, 14, 20, 44, 68, 188};

This sequence comes from consideration of an interesting (non-traditional)infinite sequence:

This infinite series comes from looking for a fourth type of Infinite series

2*A003422((n+1)/2) if n is odd, and owes it's life to hypergeometric type functions:A003422(n/2)+A003422(1+n/2) if n is even.

Sum[1/Limit[Binomial[n, m], n -> Infinity], {m, 0, Infinity}]

Mathematica can't do it:

I get terms like:middle is zero:

Limit[1/Binomial[2*n, n], n -> Infinity]=0

{1,1,1/2,1/6,...0,....1/6,1/2,1,1}

which would give limit 2*Exp[1],

but doing:

a = Table[N[Sum[1/Binomial[n, m], {m, 0, n}]], {n, 1, 1000}];

it looks like it goes toward 2 instead.

f[n_, m_] := If[m (nonascii character here) Floor[n/2], 1/m!, 1/(n - m)! ]

The conjecture is that :

Limit[Sum[1/Binomial[n, m], {m, 0, n}]] - Sum[f[n, m], {m, 0, n}]/Exp[1],n->Infinity]=0

It is by inverting the series function that I get this sequence.

FORMULA

fT(n,m) =If[ A000142(m (nonascii character here) Floorif m<=[n/2], = A000142(n-m) if m!, (>[n - /2], 0<=m)! ]<=n.

Conjecture: limit_{n->infinity} sum_{m=0..n} ( 1/binomial(n,m) - T(n,m) ) = 0.

T(n,m) = T(n,n-m).

EXAMPLE

{1},

1,

{1, 1},,

{1, 1, 1},,

{1, 1, 1, 1},,

{1, 1, 2, 1, 1},,

{1, 1, 2, 2, 1, 1},,

{1, 1, 2, 6, 2, 1, 1},,

{1, 1, 2, 6, 6, 2, 1, 1},,

{1, 1, 2, 6, 24, 6, 2, 1,1},,

{1, 1, 2, 6, 24, 24, 6, 2, 1, 1},,

{1, 1, 2, 6, 24, 120, 24, 6, 2, 1, 1}

MATHEMATICA

g[n_, m_] := If[m (nonascii character here) <= Floor[n/2], m!, (n - m)! ]; w = Table[Table[g[n, m], {m, 0, n}], {n, 0, 10}]; Flatten[w] Table[Apply[Plus, Table[g[n, m], {m, 0, n}]], {n, 0, 10}]

KEYWORD

nonn,uned,easy,tabl,new

EXTENSIONS

Non-Ascii characters corrected, offset set to 0, reported Mma experiments removed - The Assoc. Editors of the OEIS, Oct 31 2009

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

Triangular sequence from a symmetrical factorial function: f(n,m)=If[m (nonascii character here) Floor[n/2], m!, (n - m)! ].

COMMENTS

f[n_, m_] := If[m (nonascii character here) Floor[n/2], 1/m!, 1/(n - m)! ]

FORMULA

f(n,m)=If[m (nonascii character here) Floor[n/2], m!, (n - m)! ].

MATHEMATICA

g[n_, m_] := If[m (nonascii character here) Floor[n/2], m!, (n - m)! ]; w = Table[Table[g[n, m], {m, 0, n}], {n, 0, 10}]; Flatten[w] Table[Apply[Plus, Table[g[n, m], {m, 0, n}]], {n, 0, 10}]

KEYWORD

nonn,uned,tabl,new

#1 by N. J. A. Sloane at Sun Jun 29 03:00:00 EDT 2008
NAME

Triangular sequence from a symmetrical factorial function: f(n,m)=If[m �≁� Floor[n/2], m!, (n - m)! ].

DATA

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 2, 1, 1, 1, 1, 2, 6, 2, 1, 1, 1, 1, 2, 6, 6, 2, 1, 1, 1, 1, 2, 6, 24, 6, 2, 1, 1, 1, 1, 2, 6, 24, 24, 6, 2, 1, 1, 1, 1, 2, 6, 24, 120, 24, 6, 2, 1, 1

OFFSET

1,13

COMMENTS

Row sums:

{1, 2, 3, 4, 6, 8, 14, 20, 44, 68, 188};

This sequence comes from consideration of an interesting (non-traditional)infinite sequence:

This infinite series comes from looking for a fourth type of Infinite series

and owes it's life to hypergeometric type functions:

Sum[1/Limit[Binomial[n, m], n -> Infinity], {m, 0, Infinity}]

Mathematica can't do it:

I get terms like:middle is zero:

Limit[1/Binomial[2*n, n], n -> Infinity]=0

{1,1,1/2,1/6,...0,....1/6,1/2,1,1}

which would give limit 2*Exp[1],

but doing:

a = Table[N[Sum[1/Binomial[n, m], {m, 0, n}]], {n, 1, 1000}];

it looks like it goes toward 2 instead.

f[n_, m_] := If[m �≁� Floor[n/2], 1/m!, 1/(n - m)! ]

The conjecture is that :

Limit[Sum[1/Binomial[n, m], {m, 0, n}]] - Sum[f[n, m], {m, 0, n}]/Exp[1],n->Infinity]=0

It is by inverting the series function that I get this sequence.

FORMULA

f(n,m)=If[m �≁� Floor[n/2], m!, (n - m)! ].

EXAMPLE

{1},

{1, 1},

{1, 1, 1},

{1, 1, 1, 1},

{1, 1, 2, 1, 1},

{1, 1, 2, 2, 1, 1},

{1, 1, 2, 6, 2, 1, 1},

{1, 1, 2, 6, 6, 2, 1, 1},

{1, 1, 2, 6, 24, 6, 2, 1,1},

{1, 1, 2, 6, 24, 24, 6, 2, 1, 1},

{1, 1, 2, 6, 24, 120, 24, 6, 2, 1, 1}

MATHEMATICA

g[n_, m_] := If[m �≁� Floor[n/2], m!, (n - m)! ]; w = Table[Table[g[n, m], {m, 0, n}], {n, 0, 10}]; Flatten[w] Table[Apply[Plus, Table[g[n, m], {m, 0, n}]], {n, 0, 10}]

KEYWORD

nonn,uned,tabl

AUTHOR

Roger L. Bagula and Gary W. Adamson (rlbagulatftn(AT)yahoo.com), May 30 2008

STATUS

approved