A268266 - OEIS

%I #4 Jan 29 2016 12:51:46

%S 129,1918,18804,126591,619490,2377935,7594224,21042479,52119726,

%T 117925215,247685420,488872479,915404154,1638353711,2819638440,

%U 4689195855,7566196934,11884886079,18225677796,27352180415,40254857490

%N Number of length-(7+1) 0..n arrays with new repeated values introduced in sequential order starting with zero.

%C Row 7 of A268261.

%H R. H. Hardin, <a href="/A268266/b268266.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = n^8 + n^7 + 7*n^6 + 6*n^5 + 30*n^4 + 20*n^3 + 50*n^2 + 20*n + 15 for n>2

%e Some solutions for n=4

%e ..2....0....0....3....2....1....0....2....0....1....4....3....1....3....1....1

%e ..3....4....4....1....3....0....1....4....2....0....1....1....3....0....0....2

%e ..4....3....3....3....1....1....3....0....4....4....2....4....2....2....4....0

%e ..1....2....0....1....4....2....4....0....2....1....0....2....4....1....0....0

%e ..3....3....4....0....2....4....0....4....4....0....3....1....2....2....0....2

%e ..0....4....1....3....1....2....0....2....1....3....0....3....4....4....1....3

%e ..3....0....0....0....2....1....1....1....0....0....2....2....1....2....4....0

%e ..0....0....1....4....3....2....1....2....2....3....0....1....3....4....2....3

%Y Cf. A268261.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 29 2016