login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo

Thanks to everyone who made a donation during our annual appeal!
To see the list of donors, or make a donation, see the OEIS Foundation home page.

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A079959 Number of permutations satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..n, with k=1, r=5, I={2,4}. 0
1, 1, 2, 3, 6, 10, 19, 33, 60, 106, 191, 340, 610, 1089, 1950, 3485, 6236, 11150, 19946, 35670, 63802, 114107, 204091, 365018, 652857, 1167652, 2088402, 3735179, 6680529, 11948378, 21370166, 38221375, 68360472, 122265404, 218676571 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

Number of compositions (ordered partitions) of n into elements of the set {1,2,4,6}.

REFERENCES

D. H. Lehmer, Permutations with strongly restricted displacements. Combinatorial theory and its applications, II (Proc. Colloq., Balatonfured, 1969), pp. 755-770. North-Holland, Amsterdam, 1970.

LINKS

Table of n, a(n) for n=0..34.

Vladimir Baltic, On the number of certain types of strongly restricted permutations, Applicable Analysis and Discrete Mathematics Vol. 4, No 1 (2010), 119-135

Index entries for linear recurrences with constant coefficients, signature (1,1,0,1,0,1).

FORMULA

a(n) = a(n-1)+a(n-2)+a(n-4)+a(n-6) G.f.: -1/(x^6+x^4+x^2+x-1)

CROSSREFS

Cf. A002524-A002529, A072827, A072850-A072856, A079955-A080014.

Sequence in context: A244742 A007473 A014595 * A282583 A028495 A136752

Adjacent sequences:  A079956 A079957 A079958 * A079960 A079961 A079962

KEYWORD

nonn

AUTHOR

Vladimir Baltic, Feb 19 2003

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified January 22 22:16 EST 2020. Contains 331166 sequences. (Running on oeis4.)