|
|
A002695
|
|
P_n'(3), where P_n is n-th Legendre polynomial.
(Formerly M4642 N1985)
|
|
6
|
|
|
1, 9, 66, 450, 2955, 18963, 119812, 748548, 4637205, 28537245, 174683718, 1064611782, 6464582943, 39132819495, 236256182280, 1423046656008, 8554078990377, 51327262010673, 307488810131530, 1839455028693450
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
REFERENCES
|
H. Bateman, Some problems in potential theory, Messenger Math., 52 (1922), 71-78.
N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
|
|
LINKS
|
|
|
FORMULA
|
a(n) = Gegenbauer_C(n,3/2,3). - Paul Barry, Apr 20 2009
D-finite with recurrence: -n*a(n-2) + 3*(2*n-1)*a(n-1) + (1-n)*a(n) = 0. - Vaclav Kotesovec, Oct 04 2012
a(n) ~ (3+2*sqrt(2))^n*sqrt(n)/(4*sqrt(2*Pi)*sqrt(3*sqrt(2)-4)). - Vaclav Kotesovec, Oct 04 2012
a(n) = Sum_{i=1..n+1} i*binomial(n+i+1,i)*binomial(n+1,i)/2. - Gerry Martens, Apr 08 2018
|
|
MATHEMATICA
|
Table[SeriesCoefficient[x*(1-6x+x^2)^(-3/2), {x, 0, n}], {n, 1, 20}] (* Vaclav Kotesovec, Oct 04 2012 *)
a[n_]:= Sum[(i Binomial[n+i+1, i] Binomial[n+1, i]), {i, 1, n+1}]/2
|
|
PROG
|
(PARI)
N = 66; x = 'x + O('x^N);
gf = x*(1-6*x+x^2)^(-3/2);
Vec(gf)
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,easy
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|