cp's OEIS Frontend

A269089 T(n,k)=Number of nXk binary arrays with some element plus some horizontally, vertically or antidiagonally adjacent neighbor totalling two not more than once.

%I A269089 #4 Feb 19 2016 09:24:30
%S A269089 2,4,4,7,11,7,13,30,30,13,23,76,114,76,23,41,191,428,428,191,41,72,
%T A269089 467,1531,2238,1531,467,72,126,1127,5387,11314,11314,5387,1127,126,
%U A269089 219,2686,18590,55620,80422,55620,18590,2686,219,379,6339,63347,268289,555789
%N A269089 T(n,k)=Number of nXk binary arrays with some element plus some horizontally, vertically or antidiagonally adjacent neighbor totalling two not more than once.
%C A269089 Table starts
%C A269089 ...2.....4......7.......13.........23..........41............72............126
%C A269089 ...4....11.....30.......76........191.........467..........1127...........2686
%C A269089 ...7....30....114......428.......1531........5387.........18590..........63347
%C A269089 ..13....76....428.....2238......11314.......55620........268289........1274435
%C A269089 ..23...191...1531....11314......80422......555789.......3761534.......25063389
%C A269089 ..41...467...5387....55620.....555789.....5372270......50865307......473602013
%C A269089 ..72..1127..18590...268289....3761534....50865307.....673690710.....8768989835
%C A269089 .126..2686..63347..1274435...25063389...473602013....8768989835...159449028034
%C A269089 .219..6339.213490..5982734..164926651..4353444165..112658396453..2861259712706
%C A269089 .379.14840.713237.27813229.1074440360.39602482120.1431998499913.50787612264272
%H A269089 R. H. Hardin, <a href="/A269089/b269089.txt">Table of n, a(n) for n = 1..1404</a>
%F A269089 Empirical for column k:
%F A269089 k=1: a(n) = 2*a(n-1) +a(n-2) -2*a(n-3) -a(n-4)
%F A269089 k=2: a(n) = 2*a(n-1) +3*a(n-2) -2*a(n-3) -6*a(n-4) -4*a(n-5) -a(n-6)
%F A269089 k=3: [order 10]
%F A269089 k=4: [order 16]
%F A269089 k=5: [order 26]
%F A269089 k=6: [order 42]
%F A269089 k=7: [order 68]
%e A269089 Some solutions for n=4 k=4
%e A269089 ..0..0..0..1. .1..0..0..1. .0..0..1..0. .0..1..0..0. .0..0..0..0
%e A269089 ..1..0..0..0. .0..0..1..0. .0..0..0..1. .0..0..0..0. .0..0..0..1
%e A269089 ..0..0..0..1. .0..0..0..1. .0..1..0..0. .0..1..0..0. .1..1..0..0
%e A269089 ..1..0..0..1. .1..0..0..0. .1..0..0..0. .0..1..0..0. .0..0..0..1
%Y A269089 Column 1 is A208354(n+1).
%K A269089 nonn,tabl
%O A269089 1,1
%A A269089 _R. H. Hardin_, Feb 19 2016