A264477 - OEIS

%I #4 Nov 14 2015 15:38:15

%S 0,4,6,16,57,160,484,1449,4250,12736,37980,112684,335528,998929,

%T 2971856,8844112,26318889,78319204,233069764,693574740,2063954658,

%U 6142018600,18277651737,54391278960,161859683044,481668191001,1433366397054

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

%C Row 3 of A264476.

%H R. H. Hardin, <a href="/A264477/b264477.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-1) +10*a(n-3) -4*a(n-4) +8*a(n-5) -25*a(n-6) -4*a(n-8) +33*a(n-9) +4*a(n-10) -4*a(n-11) -10*a(n-12) -2*a(n-13) +a(n-15)

%e Some solutions for n=4

%e ..6..0..1..9..3....6..7..8..9..3....6..0..8..9..3....6..0..1..2..3

%e .11..5..2.14..4...11.12..2.14..4...11..5..2.14..4...11.12.13.14..4

%e .16.17.18.19.13....5..0..1.19.13...16.17..1.19.13....5.17.18.19..9

%e .10.15.12..7..8...10.15.16.17.18...10.15.12..7.18...10.15.16..7..8

%Y Cf. A264476.

%K nonn

%O 1,2

%A _R. H. Hardin_, Nov 14 2015