|
| |
|
|
A001888
|
|
Hit polynomials.
(Formerly M3573 N1449)
|
|
1
| |
|
|
1, 1, 1, 4, 21, 122, 849, 6719, 59873, 593686, 6483027, 77309508, 999569969, 13927664613, 208044077633, 3316415176712, 56193522437465, 1008499234742158, 19110533105114433, 381290148293261075
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,4
|
|
|
REFERENCES
| J. Riordan, ``The enumeration of permutations with three-ply staircase restrictions,'' unpublished memorandum, Bell Telephone Laboratories, Murray Hill, NJ, Oct 1963.
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).
|
|
|
CROSSREFS
| Second column of A080061.
Sequence in context: A046090 A045721 A101810 * A103769 A003014 A108404
Adjacent sequences: A001885 A001886 A001887 * A001889 A001890 A001891
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com).
|
|
|
EXTENSIONS
| More terms from Vladeta Jovovic, Vladimir Baltic, (vladeta(AT)eunet.rs), Jan 23 2003
|
| |
|
|
