cp's OEIS Frontend

A229008 Number of arrays of median of three adjacent elements of some length n+2 0..4 array, with no adjacent equal elements in the latter.

%I A229008 #8 Sep 13 2013 20:15:57
%S A229008 5,23,101,359,1145,3527,10735,32907,101635,315579,982305,3059025,
%T A229008 9524031,29640801,92224095,286910991,892560177,2776725201,8638459639,
%U A229008 26874806287,83609764417,260117322353,809247413805,2517636208515,7832571212121
%N A229008 Number of arrays of median of three adjacent elements of some length n+2 0..4 array, with no adjacent equal elements in the latter.
%C A229008 Column 4 of A229012.
%H A229008 R. H. Hardin, <a href="/A229008/b229008.txt">Table of n, a(n) for n = 1..136</a>
%F A229008 Empirical: a(n) = 4*a(n-1) -a(n-2) -10*a(n-3) +7*a(n-4) +35*a(n-5) -47*a(n-6) -9*a(n-7) +106*a(n-8) -43*a(n-9) -123*a(n-10) +248*a(n-11) -30*a(n-12) -255*a(n-13) +370*a(n-14) +13*a(n-15) -396*a(n-16) +484*a(n-17) +88*a(n-18) -609*a(n-19) +715*a(n-20) -62*a(n-21) -603*a(n-22) +830*a(n-23) -305*a(n-24) -450*a(n-25) +825*a(n-26) -580*a(n-27) -91*a(n-28) +586*a(n-29) -678*a(n-30) +304*a(n-31) +130*a(n-32) -423*a(n-33) +364*a(n-34) -103*a(n-35) -83*a(n-36) +176*a(n-37) -111*a(n-38) +25*a(n-39) +37*a(n-40) -32*a(n-41) +17*a(n-42) -2*a(n-43) -4*a(n-44) +2*a(n-45) -a(n-46).
%e A229008 Some solutions for n=4
%e A229008 ..1....2....3....2....2....3....2....1....0....1....0....2....3....1....0....3
%e A229008 ..2....2....3....3....3....0....0....1....1....4....2....1....1....3....4....2
%e A229008 ..1....0....3....1....1....2....4....2....1....2....1....1....4....2....2....1
%e A229008 ..3....1....1....4....3....1....3....4....1....2....3....0....0....2....2....0
%K A229008 nonn
%O A229008 1,1
%A A229008 _R. H. Hardin_, Sep 10 2013