# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a209378 Showing 1-1 of 1 %I A209378 #13 Jul 09 2018 17:34:49 %S A209378 32,80,156,512,1076,4004,8612,33716,73028,291908,633732,2555588, %T A209378 5552900,22478852,48859652,198127364,430707716,1747864580,3799906308, %U A209378 15425772548,33536978948,136164892676,296038014980,1202040352772,2613387280388 %N A209378 1/4 the number of (n+1) X 5 0..2 arrays with every 2 X 2 subblock having distinct edge sums. %C A209378 Column 4 of A209382. %H A209378 R. H. Hardin, Table of n, a(n) for n = 1..210 %F A209378 Empirical: a(n) = 3*a(n-1) + 12*a(n-2) - 42*a(n-3) - 24*a(n-4) + 156*a(n-5) - 48*a(n-6) - 168*a(n-7) + 112*a(n-8). %F A209378 Empirical g.f.: 4*x*(8 - 4*x - 117*x^2 + 107*x^3 + 449*x^4 - 472*x^5 - 502*x^6 + 548*x^7) / ((1 - x)*(1 - 2*x)*(1 - 2*x^2)*(1 - 12*x^2 + 28*x^4)). - _Colin Barker_, Jul 09 2018 %e A209378 Some solutions for n=4: %e A209378 ..0..2..2..2..0....2..0..2..0..2....1..2..2..2..1....0..0..2..1..2 %e A209378 ..0..1..0..1..0....1..0..1..0..1....0..0..1..0..0....2..1..2..0..2 %e A209378 ..2..2..2..2..2....2..2..2..0..2....1..2..2..2..1....2..0..2..1..2 %e A209378 ..0..1..0..1..0....1..0..1..0..1....0..0..1..0..0....2..1..2..0..2 %e A209378 ..0..2..0..2..2....2..0..2..2..2....1..2..2..2..1....0..0..2..1..2 %Y A209378 Cf. A209382. %K A209378 nonn %O A209378 1,1 %A A209378 _R. H. Hardin_, Mar 07 2012 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE