OFFSET
0,3
LINKS
V. Jelinek, T. Mansour, M. Shattuck, On multiple pattern avoiding set partitions, Adv. Appl. Math. 50 (2) (2013) 292-326, Example 4.16 H_{1121} and example 4.17 L_{1121}.
Index entries for linear recurrences with constant coefficients, signature (4,-4,0,2).
FORMULA
G.f (1-x-x^2)*(1-x)^2/(1-4*x+4*x^2-2*x^4), correcting a sign in denominators of the publication.
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
R. J. Mathar, Jan 12 2013
STATUS
approved