A236278 - OEIS

%I #4 Jan 21 2014 12:34:46

%S 42,208,208,1048,1770,1048,5328,15434,15434,5328,27168,137142,232736,

%T 137142,27168,138720,1226262,3604782,3604782,1226262,138720,708640,

%U 11005062,56299040,98027150,56299040,11005062,708640,3620768,98896922

%N T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with the upper median unequal to the lower median in every 2X2 subblock

%C Table starts

%C .......42.........208...........1048..............5328................27168

%C ......208........1770..........15434............137142..............1226262

%C .....1048.......15434.........232736...........3604782.............56299040

%C .....5328......137142........3604782..........98027150...........2691633954

%C ....27168.....1226262.......56299040........2691633954.........130035577996

%C ...138720....11005062......884625654.......74525190422........6347865358508

%C ...708640....98896922....13930389246.....2069437793694......310963707906138

%C ..3620768...889370642...219666732130....57582849812178....15274560591620964

%C .18501536..8000222410..3465756760168..1603546636521534...751073391280421888

%C .94542752.71974995478.54697571104400.44677821271613598.36957869813931113212

%H R. H. Hardin, <a href="/A236278/b236278.txt">Table of n, a(n) for n = 1..161</a>

%F Empirical for column k:

%F k=1: a(n) = 5*a(n-1) +4*a(n-2) -16*a(n-3) -8*a(n-4)

%F k=2: [order 9]

%F k=3: [order 25]

%F k=4: [order 65]

%e Some solutions for n=2 k=4

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

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

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

%K nonn,tabl

%O 1,1

%A _R. H. Hardin_, Jan 21 2014