|
|
A156711
|
|
a(n) = 144*n^2 - 161*n + 45.
|
|
2
|
|
|
28, 299, 858, 1705, 2840, 4263, 5974, 7973, 10260, 12835, 15698, 18849, 22288, 26015, 30030, 34333, 38924, 43803, 48970, 54425, 60168, 66199, 72518, 79125, 86020, 93203, 100674, 108433, 116480, 124815, 133438, 142349, 151548, 161035
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
|
|
LINKS
|
|
|
FORMULA
|
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3).
G.f.: x*(-28 - 215*x - 45*x^2)/(x-1)^3.
|
|
MATHEMATICA
|
LinearRecurrence[{3, -3, 1}, {28, 299, 858}, 40]
|
|
PROG
|
(Magma) I:=[28, 299, 858]; [n le 3 select I[n] else 3*Self(n-1)-3*Self(n-2)+1*Self(n-3): n in [1..40]];
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,easy
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|