|
| |
|
|
A099570
|
|
Expansion of ((1+x)^2-x^3)/(1+x)^2.
|
|
2
| |
|
|
1, 0, 0, -1, 2, -3, 4, -5, 6, -7, 8, -9, 10, -11, 12, -13, 14, -15, 16, -17, 18, -19, 20, -21, 22, -23, 24, -25, 26, -27, 28, -29, 30, -31, 32, -33, 34, -35, 36, -37, 38, -39, 40, -41, 42, -43, 44, -45, 46, -47, 48, -49, 50, -51, 52, -53, 54, -55, 56, -57, 58, -59, 60, -61, 62, -63, 64, -65, 66, -67, 68, -69, 70, -71, 72, -73
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 0,5
|
|
|
COMMENTS
| Row sums of number triangle A099569.
|
|
|
FORMULA
| a(n)=2*0^n-sum{k=0..n, k*binomial(n, k)(-1)^(n-k)}+(n-2)*(-1)^n; a(n)=-2a(n-1)-a(n-2), n>3, a(0)=1, a(1)=0, a(2)=0, a(3)=-1.
|
|
|
CROSSREFS
| Sequence in context: A173474 A023443 * A114142 A020725 A119972 A131738
Adjacent sequences: A099567 A099568 A099569 * A099571 A099572 A099573
|
|
|
KEYWORD
| easy,sign
|
|
|
AUTHOR
| Paul Barry (pbarry(AT)wit.ie), Oct 22 2004
|
| |
|
|
