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A168619
Triangle T(n,k) read by rows with the coefficient [x^k] of the polynomial (x+1)^n + (2*n-3) *( (x+1)^n -x^n -1 ) in column k, row n.
2
1, 1, 1, 1, 4, 1, 1, 12, 12, 1, 1, 24, 36, 24, 1, 1, 40, 80, 80, 40, 1, 1, 60, 150, 200, 150, 60, 1, 1, 84, 252, 420, 420, 252, 84, 1, 1, 112, 392, 784, 980, 784, 392, 112, 1, 1, 144, 576, 1344, 2016, 2016, 1344, 576, 144, 1, 1, 180, 810, 2160, 3780, 4536, 3780, 2160, 810
OFFSET
0,5
COMMENTS
The term T(0,0) is defined to be 1.
Row sums are s(n) = 1, 2, 6, 26, 86, 242, 622, 1514, 3558, 8162, 18398,... (apparently with s(n) = 6*s(n-1) -13*s(n-2) +12*s(n-3)-4*s(n-4)).
EXAMPLE
1;
1, 1;
1, 4, 1;
1, 12, 12, 1;
1, 24, 36, 24, 1;
1, 40, 80, 80, 40, 1;
1, 60, 150, 200, 150, 60, 1;
1, 84, 252, 420, 420, 252, 84, 1;
1, 112, 392, 784, 980, 784, 392, 112, 1;
1, 144, 576, 1344, 2016, 2016, 1344, 576, 144, 1;
1, 180, 810, 2160, 3780, 4536, 3780, 2160, 810, 180, 1;
MAPLE
A168619 := proc(n, k)
if n = 0 then
1;
else
(1+x)^n + (2*n-3)*((1+x)^n-x^n-1) ;
coeftayl(%, x=0, k) ;
end if;
end proc: # R. J. Mathar, Jul 11 2012
MATHEMATICA
p[x_, n_] := (x + 1)^n + If[n == 0, 0, (2*n - 3)]*((x + 1)^n - x^n - 1)
a = Table[CoefficientList[p[x, n], x], {n, 0, 10}];
Flatten[a]
CROSSREFS
Sequence in context: A154372 A080416 A213166 * A099759 A350819 A072590
KEYWORD
nonn,tabl
AUTHOR
STATUS
approved