cp's OEIS Frontend

A189323 Number of nondecreasing arrangements of n+2 numbers in 0..6 with the last equal to 6 and each after the second equal to the sum of one or two of the preceding four.

%I A189323 #8 May 02 2018 09:22:45
%S A189323 10,18,36,64,110,179,275,393,528,676,836,1008,1192,1388,1596,1816,
%T A189323 2048,2292,2548,2816,3096,3388,3692,4008,4336,4676,5028,5392,5768,
%U A189323 6156,6556,6968,7392,7828,8276,8736,9208,9692,10188,10696,11216,11748,12292,12848
%N A189323 Number of nondecreasing arrangements of n+2 numbers in 0..6 with the last equal to 6 and each after the second equal to the sum of one or two of the preceding four.
%C A189323 Column 6 of A189326.
%H A189323 R. H. Hardin, <a href="/A189323/b189323.txt">Table of n, a(n) for n = 1..200</a>
%F A189323 Empirical: a(n) = 6*n^2 + 34*n - 264 for n>8.
%F A189323 Empirical g.f.: x*(10 - 12*x + 12*x^2 + 8*x^4 + 5*x^5 + 4*x^6 - 5*x^7 - 5*x^8 - 4*x^9 - x^10) / (1 - x)^3. - _Colin Barker_, May 02 2018
%e A189323 Some solutions for n=3:
%e A189323 ..1....1....2....2....1....3....1....2....2....0....1....1....3....2....1....1
%e A189323 ..5....6....3....4....4....6....5....2....4....3....3....3....3....3....5....3
%e A189323 ..5....6....3....4....5....6....5....4....4....3....4....3....3....3....6....3
%e A189323 ..5....6....6....4....5....6....6....6....6....3....5....4....6....3....6....6
%e A189323 ..6....6....6....6....6....6....6....6....6....6....6....6....6....6....6....6
%Y A189323 Cf. A189326.
%K A189323 nonn
%O A189323 1,1
%A A189323 _R. H. Hardin_, Apr 20 2011