A247921 - OEIS

%I #7 Mar 15 2023 11:07:35

%S 203,529,1387,3649,9611,25265,66443,174817,460139,1211409,3189259,

%T 8396641,22107499,58209297,153270315,403580257,1062688075,2798238641,

%U 7368281835,19402138145,51089798827,134530145105,354246523595

%N Number of length n+4 0..2 arrays with some disjoint pairs in every consecutive five terms having the same sum.

%C Column 2 of A247927.

%H R. H. Hardin, <a href="/A247921/b247921.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 3*a(n-1) -2*a(n-3) -a(n-4) +6*a(n-5) -14*a(n-6) -13*a(n-7) -2*a(n-8) +8*a(n-9) -4*a(n-10) +8*a(n-11) +8*a(n-12).

%e Some solutions for n=6

%e ..0....0....1....2....1....1....0....2....2....0....0....1....1....1....2....2

%e ..1....2....2....0....2....1....1....1....1....2....2....1....0....0....1....1

%e ..1....2....2....1....1....1....1....0....2....0....1....2....1....1....0....1

%e ..0....1....1....1....2....1....1....1....1....1....0....2....0....0....0....1

%e ..2....0....0....0....0....2....1....2....1....1....1....0....2....0....1....0

%e ..1....1....1....1....0....1....0....1....1....0....0....0....2....0....1....0

%e ..0....0....2....2....1....2....1....1....1....0....1....2....1....0....1....0

%e ..1....2....1....0....1....2....1....1....0....0....1....1....0....0....1....0

%e ..0....2....2....1....1....1....1....1....2....0....1....1....1....1....0....0

%e ..2....1....2....1....2....1....2....1....2....0....1....2....1....1....2....2

%Y Cf. A247927.

%K nonn

%O 1,1

%A _R. H. Hardin_, Sep 26 2014