|
|
A132074
|
|
Row sums of triangle A132073.
|
|
2
|
|
|
1, 4, 9, 16, 27, 46, 81, 148, 279, 538, 1053, 2080, 4131, 8230, 16425, 32812, 65583, 131122, 262197, 524344, 1048635, 2097214, 4194369, 8388676, 16777287, 33554506, 67108941, 134217808, 268435539, 536870998, 1073741913, 2147483740
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,2
|
|
LINKS
|
|
|
FORMULA
|
Binomial transform of [1, 3, 2, 0, 2, 0, 2, 0, 2, ...].
G.f.:= (2*x^2 + 2*x^3 - 1)/((2*x-1)*(x-1)^2).
a(n) = 2^n + 3*n - 1, n > 0. (End)
|
|
EXAMPLE
|
a(4) = 27 = sum of row 4 terms of triangle A132073: (5 + 5 + 7 + 5 + 5).
a(4) = 27 = (1, 4, 6, 4, 1) dot (1, 3, 2, 0, 2) = (1 + 12 + 12 + 0 + 2).
|
|
MATHEMATICA
|
CoefficientList[Series[(2*x^2+2*x^3-1)/((2*x-1)*(x-1)^2), {x, 0, 40}], x] (* Vincenzo Librandi, Jul 06 2012 *)
|
|
PROG
|
(Magma) I:=[1, 4, 9, 16]; [n le 4 select I[n] else 4*Self(n-1)-5*Self(n-2)+2*Self(n-3): n in [1..40]]; // Vincenzo Librandi, Jul 06 2012
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,easy
|
|
AUTHOR
|
|
|
EXTENSIONS
|
|
|
STATUS
|
approved
|
|
|
|