|
|
A158501
|
|
Hankel transform of A158500.
|
|
2
|
|
|
1, 0, 25, -24, 105, -104, 273, -272, 561, -560, 1001, -1000, 1625, -1624, 2465, -2464, 3553, -3552, 4921, -4920, 6601, -6600, 8625, -8624, 11025, -11024, 13833, -13832, 17081, -17080, 20801, -20800, 25025, -25024, 29785, -29784, 35113, -35112, 41041, -41040
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,3
|
|
LINKS
|
|
|
FORMULA
|
G.f.: (1+x+22*x^2-2*x^3+9*x^4+x^5) / ((1-x)^3*(1+x)^4).
a(n) = -a(n-1)+3*a(n-2)+3*a(n-3)-3*a(n-4)-3*a(n-5)+a(n-6)+a(n-7).
a(n) = (n+1)*(2*(-1)^n*n^2+4*(-1)^n*n+3*n+3)/3.
a(n) = (2*n^3+9*n^2+10*n+3)/3 for n even.
a(n) = (-2*n^3-3*n^2+2*n+3)/3 for n odd.
(End)
|
|
MATHEMATICA
|
LinearRecurrence[{-1, 3, 3, -3, -3, 1, 1}, {1, 0, 25, -24, 105, -104, 273}, 40] (* Harvey P. Dale, Aug 19 2012 *)
|
|
PROG
|
(PARI) Vec((1+x+22*x^2-2*x^3+9*x^4+x^5)/((1-x)^3*(1+x)^4) + O(x^50)) \\ Colin Barker, Jan 29 2016
|
|
CROSSREFS
|
|
|
KEYWORD
|
easy,sign
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|