|
%I #9 May 20 2018 13:54:51
%S 8,36,164,750,3434,15724,71970,329455,1508139,6903702,31602661,
%T 144665637,662227235,3031438038,13876832881,63523149100,290786125630,
%U 1331114279973,6093362338144,27893220846536,127685131134366,584496598744029
%N Number of 0..7 arrays x(0..n-1) of n elements with each no smaller than the sum of its previous elements modulo 8.
%C Column 7 of A200251.
%H R. H. Hardin, <a href="/A200250/b200250.txt">Table of n, a(n) for n = 1..134</a>
%F Empirical: a(n) = a(n-1) +9*a(n-2) +24*a(n-3) +36*a(n-4) +35*a(n-5) +21*a(n-6) +7*a(n-7) +a(n-8).
%F Empirical g.f.: x*(2 + x)*(2 + 2*x + x^2)*(2 + 4*x + 6*x^2 + 4*x^3 + x^4) / (1 - x - 9*x^2 - 24*x^3 - 36*x^4 - 35*x^5 - 21*x^6 - 7*x^7 - x^8). - _Colin Barker_, May 20 2018
%e Some solutions for n=6:
%e ..3....1....6....3....2....3....2....1....0....6....3....3....0....7....2....1
%e ..6....3....7....7....6....5....6....4....3....6....7....5....2....7....6....4
%e ..7....6....7....7....4....2....3....5....6....7....6....1....7....7....3....5
%e ..5....2....4....1....5....2....6....7....3....6....6....1....5....6....6....6
%e ..5....5....1....3....6....5....1....3....7....2....6....3....6....7....5....2
%e ..7....5....5....6....7....3....5....4....5....7....5....6....7....7....7....7
%Y Cf. A200251.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 15 2011
| 