|
Search: id:A101551
|
|
|
| A101551 |
|
C(n-2,2)+C(n-5,5)+...+C(n-(3*floor((n-3)/3)+2),3*floor((n-3)/3)+2). |
|
+0
4
|
|
| 0, 0, 0, 0, 1, 3, 6, 10, 15, 21, 29, 42, 66, 111, 192, 330, 554, 906, 1452, 2303, 3651, 5826, 9382, 15225, 24807, 40431, 65748, 106584, 172321, 278184, 448980, 725140, 1172412, 1897380, 3072365, 4975551, 8055918, 13038606, 21096027, 34125561
(list; graph; listen)
|
|
|
OFFSET
|
0,6
|
|
|
FORMULA
|
G.f.: x^4/((1-x)^3-x^6); a(n)=sum{k=0..n, if(mod(k+1, 3)=0, C(n-k, k), 0)}.
a(n+2)=sum{k=0..floor(n/6), binomial(n-3k, 3k+2)}. - Paul Barry (pbarry(AT)wit.ie), Jan 13 2005
|
|
CROSSREFS
|
Cf. A024490, A101552.
Sequence in context: A062099 A115650 A025745 this_sequence A051166 A061304 A109442
Adjacent sequences: A101548 A101549 A101550 this_sequence A101552 A101553 A101554
|
|
KEYWORD
|
easy,nonn
|
|
AUTHOR
|
Paul Barry (pbarry(AT)wit.ie), Dec 06 2004
|
|
|
Search completed in 0.002 seconds
|
