|
Search: id:A006932
|
|
|
| A006932 |
|
Number of permutations with strong fixed points.
(Formerly M2862)
|
|
+0
2
|
|
| 1, 1, 3, 10, 43, 223, 1364, 9643, 77545, 699954, 7013079, 77261803, 928420028, 12085410927, 169413357149, 2544367949634, 40758600588283, 693684669653911, 12499734669634036, 237734433597317987, 4759174459355303521
(list; graph; listen)
|
|
|
OFFSET
|
0,3
|
|
|
REFERENCES
|
Problem E3467, Amer. Math. Monthly, 100 (1993), 800-801.
K. Wayland, personal communication.
Stanley, R. P., Enumerative Combinatorics, Volume 1 (1986), p. 49.
|
|
MATHEMATICA
|
t1 := sum(n!*x^n, n=0..100): F := series(t1/(1+x*t1), x, 100): for i from 1 to 40 do printf(`%d, `, i!-coeff(F, x, i)) od:
|
|
CROSSREFS
|
Cf. A052186.
Adjacent sequences: A006929 A006930 A006931 this_sequence A006933 A006934 A006935
Sequence in context: A030890 A030833 A030971 this_sequence A001040 A032269 A041737
|
|
KEYWORD
|
nonn,easy,nice
|
|
AUTHOR
|
njas
|
|
EXTENSIONS
|
More terms and Maple code from James A. Sellers (sellersj(AT)math.psu.edu), Mar 13 2000
|
|
|
Search completed in 0.002 seconds
|
