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A180907 Number of sequences of n integers p(i) i=0..n-1 with 0<=p(i)<=2*i and -2<p(i)-p(i-1)<=2 1

%I

%S 1,3,11,42,163,639,2520,9976,39595,157441,626859,2498318,9964308,

%T 39764292,158756360,634044576,2532959099,10121210373,40449588625,

%U 161680869046,646330342699,2584001013295,10331554755044,41311180250504

%N Number of sequences of n integers p(i) i=0..n-1 with 0<=p(i)<=2*i and -2<p(i)-p(i-1)<=2

%C Paths down a n-high staggered-grid minimally right-leaning right triangle with interior neighbor fanout 2*2

%C Column 2 of A180915

%D M. Wallner, Lattice Path Combinatorics, Diplomarbeit, Institut für Diskrete Mathematik und Geometrie der Technischen Universität Wien, 2013; http://dmg.tuwien.ac.at/drmota/Thesis_Wallner.pdf

%H R. H. Hardin, <a href="/A180907/b180907.txt">Table of n, a(n) for n=1..100</a>

%K nonn

%O 1,2

%A _R. H. Hardin_ Sep 23 2010

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Last modified January 20 19:53 EST 2020. Contains 331096 sequences. (Running on oeis4.)