cp's OEIS Frontend

A026083 a(n) = number of (s(0), s(1), ..., s(n)) such that every s(i) is an integer, s(0) = 0 = s(n), |s(i) - s(i-1)| = 1 for i = 1,2,3; |s(i) - s(i-1)| <= 1 for i >= 4. Also a(n) = T(n,n), where T is the array defined in A026082.

%I A026083 #9 Jun 22 2013 15:43:17
%S A026083 6,12,38,104,300,856,2464,7104,20550,59580,173118,503960,1469546,
%T A026083 4291644,12550290,36746592,107712306,316050372,928224594,2728494360,
%U A026083 8026707864,23630376000,69614498268,205212650272,605292727450,1786351811556
%N A026083 a(n) = number of (s(0), s(1), ..., s(n)) such that every s(i) is an integer, s(0) = 0 = s(n), |s(i) - s(i-1)| = 1 for i = 1,2,3; |s(i) - s(i-1)| <= 1 for i >= 4. Also a(n) = T(n,n), where T is the array defined in A026082.
%C A026083 Third differences of the central trinomial numbers (A002426). - _T. D. Noe_, Mar 16 2005
%F A026083 Conjecture: n*a(n) +(-3*n+5)*a(n-1) +(-n-6)*a(n-2) +3*(n-5)*a(n-3)=0. - _R. J. Mathar_, Jun 22 2013
%Y A026083 Equals 2 * A024998(n-1). First differences of A024997.
%K A026083 nonn
%O A026083 4,1
%A A026083 _Clark Kimberling_