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A144394 Triangle: coefficients of the symmetrical polynomial p(x,n)=((x + 1)^n - (x^n + n*x^(n - 1) + n*x + 1))/x^2. 0
6, 10, 10, 15, 20, 15, 21, 35, 35, 21, 28, 56, 70, 56, 28, 36, 84, 126, 126, 84, 36, 45, 120, 210, 252, 210, 120, 45, 55, 165, 330, 462, 462, 330, 165, 55, 66, 220, 495, 792, 924, 792, 495, 220, 66, 78, 286, 715, 1287, 1716, 1716, 1287, 715, 286, 78, 91, 364, 1001 (list; table; graph; refs; listen; history; internal format)
OFFSET

4,1

COMMENTS

Interior of Pascal's triangle, stripping out the initial 1,n and final n,1 in each row.

The first term in the sequence is T(4,0); each row has 0 <= k <= n-4.

FORMULA

T(n,k) = C(n,k+2).

EXAMPLE

{6},

{10, 10},

{15, 20, 15},

{21, 35, 35, 21},

{28, 56, 70, 56, 28},

{36, 84, 126, 126, 84, 36},

{45, 120, 210, 252, 210, 120, 45},

{55, 165, 330, 462, 462, 330, 165, 55},

{66, 220, 495, 792, 924, 792, 495, 220, 66},

{78, 286, 715, 1287, 1716, 1716, 1287, 715, 286, 78},

{91, 364, 1001, 2002, 3003, 3432, 3003, 2002, 1001, 364, 91},

{105, 455, 1365, 3003, 5005, 6435, 6435, 5005, 3003, 1365, 455, 105}

MATHEMATICA

Clear[p, x, n]; p[x_, n_] = ((x + 1)^n - (x^n + n*x^(n - 1) + n*x + 1))/x^2; Table[ExpandAll[p[x, n]], {n, 4, 15}]; Table[CoefficientList[p[x, n], x], {n, 4, 15}]; Flatten[%]

CROSSREFS

Cf. A007318, A052515 (row sums), A024746 (sorted).

Sequence in context: A175612 A024746 A111093 * A087873 A107014 A206036

Adjacent sequences:  A144391 A144392 A144393 * A144395 A144396 A144397

KEYWORD

nonn,tabl

AUTHOR

Roger L. Bagula and Gary W. Adamson (rlbagulatftn(AT)yahoo.com), Oct 02 2008

EXTENSIONS

Edited by Franklin T. Adams-Watters (FrankTAW(AT)Netscape.net), Apr 07 2010

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Last modified February 15 09:42 EST 2012. Contains 205756 sequences.