|
|
A144399
|
|
Triangle in A144385 with rows left-adjusted.
|
|
4
|
|
|
1, 1, 1, 1, 1, 3, 7, 10, 10, 1, 6, 25, 75, 175, 280, 280, 1, 10, 65, 315, 1225, 3780, 9100, 15400, 15400, 1, 15, 140, 980, 5565, 26145, 102025, 323400, 800800, 1401400, 1401400, 1, 21, 266, 2520, 19425, 125895, 695695, 3273270, 12962950
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,6
|
|
COMMENTS
|
Row n has 2n+1 terms.
|
|
LINKS
|
|
|
EXAMPLE
|
Triangle begins:
1
1, 1, 1
1, 3, 7, 10, 10
1, 6, 25, 75, 175, 280, 280
1, 10, 65, 315, 1225, 3780, 9100, 15400, 15400
|
|
MAPLE
|
b:= proc(n) option remember; expand(`if`(n=0, 1, add(
b(n-j)*binomial(n-1, j-1), j=1..min(3, n))*x))
end:
T:= (n, k)-> coeff(b(k), x, n):
|
|
MATHEMATICA
|
b[n_] := b[n] = Expand[If[n == 0, 1, Sum[b[n - j]*Binomial[n - 1, j - 1], {j, 1, Min[3, n]}]*x]];
T[n_, k_] := Coefficient[b[k], x, n];
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,tabf
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|