|
%I #9 May 05 2018 20:42:50
%S 32768,344091,882318,1481501,2089736,2698979,3308286,3917595,4526904,
%T 5136213,5745522,6354831,6964140,7573449,8182758,8792067,9401376,
%U 10010685,10619994,11229303,11838612,12447921,13057230,13666539,14275848
%N Number of lower triangles of a 5 X 5 0..n array with no element differing from any of its horizontal or vertical neighbors by more than one.
%C Row 5 of A194931.
%H R. H. Hardin, <a href="/A194934/b194934.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = 609309*n - 956877 for n>6.
%F Empirical g.f.: x*(32768 + 278555*x + 226904*x^2 + 60956*x^3 + 9052*x^4 + 1008*x^5 + 64*x^6+ 2*x^7) / (1 - x)^2. - _Colin Barker_, May 05 2018
%e Some solutions for n=2:
%e ..1..........2..........1..........0..........2..........0..........1
%e ..0.0........1.1........2.1........1.1........1.0........1.1........2.1
%e ..1.0.1......0.1.1......2.1.1......1.1.1......2.1.1......2.1.1......1.1.0
%e ..2.1.1.1....1.2.1.1....2.1.1.1....2.1.1.1....2.2.1.1....1.0.1.1....1.0.0.1
%e ..2.2.2.1.1..1.1.0.1.1..1.1.1.2.2..2.1.0.1.2..2.2.1.1.1..2.1.1.2.1..1.0.1.2.2
%Y Cf. A194931.
%K nonn
%O 1,1
%A _R. H. Hardin_, Sep 05 2011
| 