cp's OEIS Frontend

A264630 Number of (3+1)X(n+1) arrays of permutations of 0..n*4+3 with each element having directed index change -2,0 -1,0 0,-1 or 1,1.

%I A264630 #4 Nov 19 2015 06:58:42
%S A264630 2,4,13,40,125,393,1200,3759,11572,36004,111380,345489,1070564,
%T A264630 3318409,10285305,31878944,98808901,306255436,949236490,2942139012,
%U A264630 9119124333,28264569620,87605626309,271532263929,841610129904,2608557687707
%N A264630 Number of (3+1)X(n+1) arrays of permutations of 0..n*4+3 with each element having directed index change -2,0 -1,0 0,-1 or 1,1.
%C A264630 Row 3 of A264628.
%H A264630 R. H. Hardin, <a href="/A264630/b264630.txt">Table of n, a(n) for n = 1..210</a>
%F A264630 Empirical: a(n) = 6*a(n-2) +10*a(n-3) +4*a(n-4) -2*a(n-5) -a(n-6) +4*a(n-7) +18*a(n-8) +25*a(n-9) -8*a(n-10) -6*a(n-11) -10*a(n-12) +a(n-15)
%e A264630 Some solutions for n=4
%e A264630 ..1.11..7..4..9....1..2..7..4..9....5.11..3..4..9....1.11..3..4..9
%e A264630 ..6..0..8..2..3...10..0.12.18..3....6..0..1..2.14...10..0..8..2.14
%e A264630 .15..5.17.14.19...15..5..6.14..8...15.12.17..7..8...15..5..6..7.19
%e A264630 .16.10.18.12.13...16.17.11.19.13...16.10.18.19.13...16.17.18.12.13
%Y A264630 Cf. A264628.
%K A264630 nonn
%O A264630 1,1
%A A264630 _R. H. Hardin_, Nov 19 2015