A079975 Number of permutations satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..n, with k=1, r=4, I={3}.

1, 1, 2, 4, 7, 14, 26, 49, 93, 175, 331, 625, 1180, 2229, 4209, 7949, 15012, 28350, 53540, 101111, 190950, 360613, 681024, 1286127, 2428875, 4586976, 8662591, 16359466, 30895160, 58346092, 110187694, 208091537, 392984789, 742159180

Offset

0,3

Comments

Number of compositions (ordered partitions) of n into elements of the set {1,2,3,5}.

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..33.

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 (1,1,1,0,1).

Formula

Recurrence: a(n) = a(n-1)+a(n-2)+a(n-3)+a(n-5).

G.f.: -1/(x^5+x^3+x^2+x-1).

Crossrefs

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

Sequence in context: A054191 A347761 A257792 * A253511 A076739 A017996

Adjacent sequences: A079972 A079973 A079974 * A079976 A079977 A079978

Keyword

nonn,easy

Author

Vladimir Baltic, Feb 17 2003

Status

approved