|
| |
|
|
A115190
|
|
Fourth diagonal (M=4) of triangle A115154 (called Y(3,1)).
|
|
0
| |
|
|
1, 121, 1762, 20989, 235543, 2588641, 28259704, 308277688, 3369314986, 36937817182, 406378312834, 4487124168115, 49722977591155, 552884158181785, 6167643983348920, 69012419067802540, 774413615153430670
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 0,2
|
|
|
FORMULA
| a(n)= A115154(n+3,n+1), n>=0.
Recurrence: a(n)= b(n) - 9*(b(n-1)-b(n-2)), with b(n):=A064063(n+4), n>=0.
G.f.: ((-3+18*x+2*x^3) + 3*(1-9*x+9*x^2)*c(3*x))/((2+x)*x^3), with the o.g.f. c(x) of A000108 (Catalan).
|
|
|
EXAMPLE
| a(0)= 1 = 190 - 9*(25-4); a(2) = 1762 = 14506 - 9*(1606-190).
|
|
|
CROSSREFS
| Sequence in context: A206466 A137434 A175111 * A189652 A206629 A014758
Adjacent sequences: A115187 A115188 A115189 * A115191 A115192 A115193
|
|
|
KEYWORD
| nonn,easy
|
|
|
AUTHOR
| Wolfdieter Lang (wolfdieter.lang_AT_physik_DOT_uni-karlsruhe_DOT_de), Feb 23 2006
|
| |
|
|
