A237303 - OEIS

%I #6 Sep 04 2022 11:09:27

%S 2174,60958,1415117,36167196,901210126,22791851729,575227568134,

%T 14576482693268,369877014297284,9407162281076564,239676058182037015,

%U 6117763712082310839,156417272522417278315,4005650244621379842960

%N Number of (n+1) X (3+1) 0..2 arrays with the upper median of every 2 X 2 subblock equal.

%C Column 3 of A237308.

%H R. H. Hardin, <a href="/A237303/b237303.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 43*a(n-1) -18*a(n-2) -16082*a(n-3) +72844*a(n-4) +2149349*a(n-5) -12314696*a(n-6) -139508618*a(n-7) +909594476*a(n-8) +4987518611*a(n-9) -36828912362*a(n-10) -104965997369*a(n-11) +907186214335*a(n-12) +1321977598400*a(n-13) -14412156428191*a(n-14) -9371719079806*a(n-15) +152843082809134*a(n-16) +24344548877881*a(n-17) -1104327910288423*a(n-18) +159402347883427*a(n-19) +5497965043471408*a(n-20) -1805463342746870*a(n-21) -18947978604455785*a(n-22) +8172398449126226*a(n-23) +45131841373713789*a(n-24) -21490907504858002*a(n-25) -73620450553331780*a(n-26) +35141248850151952*a(n-27) +80669492461805472*a(n-28) -35813459628243072*a(n-29) -57405569590272000*a(n-30) +21963901834545152*a(n-31) +25117865772236800*a(n-32) -7529404827320320*a(n-33) -6197214595710976*a(n-34) +1268711990231040*a(n-35) +746656844742656*a(n-36) -75723964416000*a(n-37) -33061852938240*a(n-38).

%e Some solutions for n=2

%e ..0..1..1..1....1..1..2..1....0..1..1..1....2..2..2..0....2..0..2..2

%e ..1..0..2..1....2..1..0..0....0..1..1..2....1..2..2..2....1..2..2..2

%e ..1..1..1..0....1..0..2..1....2..1..1..0....0..2..2..1....2..1..2..1

%Y Cf. A237308.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 06 2014