|
|
A361962
|
|
Total number of 2-Fuss-skew paths of semilength n.
|
|
1
|
|
|
2, 14, 118, 1114, 11306, 120534, 1331374, 15103410, 174935250, 2060200670, 24595806758, 296993911690, 3620853162618, 44509749949094, 551065497319006, 6865424096224610, 86005892134892962, 1082728353985352878, 13690429445139361494, 173792202854983764666, 2214092570427696031434
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
LINKS
|
|
|
FORMULA
|
D-finite with recurrence 10*n*(2*n+1)*a(n) +3*(-121*n^2+155*n-46)*a(n-1) +3*(431*n^2-1579*n+1418)*a(n-2) -(961*n-2440) *(n-3) *a(n-3) -85*(n-3)*(n-4)*a(n-4)=0
|
|
MAPLE
|
FussSkew := proc(l, n)
local a, j, k;
a := 0 ;
for j from 0 to n do
a := a+sum( binomial(n, j) *binomial(j, k) *binomial(n*(l-1), n-2*j+k-1)
* 3^k*2^(n*(l-2)+2*j-k+1), k=0..j) ;
end do:
a/n ;
end proc:
seq(FussSkew(2, n), n=1..40) ;
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,easy
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|