|
| |
|
|
A005800
|
|
Generalized Euler numbers of type 3^2n.
(Formerly M2188)
|
|
0
| |
|
|
1, 2, 2248, 54103952, 9573516562048, 7512502267832874752, 19387585646491113265435648, 134942950050961684035671842506752, 2199105667698535717737352110310013698048
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 0,2
|
|
|
REFERENCES
| Gessel, Ira M.; Symmetric functions and P-recursiveness. J. Combin. Theory Ser. A 53 (1990), no. 2, 257-285.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
|
|
|
FORMULA
| a(n) = 1/36^n * sum_{i=0..2*n} binomial(2*n, i) * A000364(n+i)
|
|
|
MATHEMATICA
| a[n_] := Sum[Binomial[2n, i]Abs[EulerE[2(n+i)]], {i, 0, 2n}]/36^n
|
|
|
CROSSREFS
| Sequence in context: A028487 A073476 A051103 * A200170 A133074 A135234
Adjacent sequences: A005797 A005798 A005799 * A005801 A005802 A005803
|
|
|
KEYWORD
| nonn,easy
|
|
|
AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com), Simon Plouffe (simon.plouffe(AT)gmail.com)
|
|
|
EXTENSIONS
| Edited by Dean Hickerson (dean.hickerson(AT)yahoo.com), Dec 10 2002
|
| |
|
|