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%I #3 Mar 31 2012 12:35:48
%S 1,10,144,2240,36402,605600,10231704,174721408,3007128087,52066422332,
%T 905751324518,15816420350420,277052021262480,4865694946445860,
%U 85641691341319812,1510236415306298800,26675550244540566147
%N Number of sequences of n integers p(i) i=0..n-1 with 0<=p(i)<=9*i and -9<p(i)-p(i-1)<=9
%C Paths down a n-high staggered-grid minimally right-leaning right triangle with interior neighbor fanout 2*9
%C Column 9 of A180915
%H R. H. Hardin, <a href="/A180914/b180914.txt">Table of n, a(n) for n=1..100</a>
%K nonn
%O 1,2
%A _R. H. Hardin_ Sep 23 2010