A200274 - OEIS

%I #7 Jan 31 2022 16:40:03

%S 2,5,8,13,18,37,64,97,140,207,286,399,528,687,878,1127,1408,1749,2130,

%T 2607,3128,3743,4414,5191,6056,7067,8156,9387,10706,12241,13876,15717,

%U 17670,19829,22172,24787,27542,30571,33752,37317,41058,45153,49440,54073

%N Number of 0..n arrays x(0..6) of 7 elements with zero 4th differences.

%C Row 5 of A200272.

%H R. H. Hardin, <a href="/A200274/b200274.txt">Table of n, a(n) for n = 1..200</a>

%F Empirical: a(n) = a(n-5) +a(n-9) +a(n-10) -a(n-14) -a(n-15) -a(n-19) +a(n-20) +a(n-24) -a(n-25) -a(n-29) -a(n-30) +a(n-34) +a(n-35) +a(n-36) +a(n-39) -a(n-41) -a(n-44) -a(n-45) -a(n-46) +a(n-50) +a(n-51) +a(n-55) -a(n-56) -a(n-60) +a(n-61) +a(n-65) +a(n-66) -a(n-70) -a(n-71) -a(n-75) +a(n-80).

%e Some solutions for n=6

%e ..4....6....0....5....5....2....1....3....4....1....3....0....5....3....6....2

%e ..2....3....4....6....1....2....0....5....6....1....1....6....5....1....4....0

%e ..2....1....4....5....0....2....1....6....6....1....1....6....5....0....4....0

%e ..3....0....2....3....1....2....3....6....5....1....2....3....5....0....5....1

%e ..4....0....0....1....3....2....5....5....4....1....3....0....5....1....6....2

%e ..4....1....0....0....5....2....6....3....4....1....3....0....5....3....6....2

%e ..2....3....4....1....6....2....5....0....6....1....1....6....5....6....4....0

%Y Cf. A200272.

%K nonn

%O 1,1

%A _R. H. Hardin_, Nov 15 2011