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A228481 Number of nX7 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or antidiagonally. 2

%I #7 Sep 01 2013 18:27:19

%S 13,88,1181,13050,152373,1748684,20185842,232542935,2680777055,

%T 30897168815,356129525933,4104762592860,47311923541451,

%U 545321432832844,6285425006257311,72446383973495105,835023655383918595

%N Number of nX7 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or antidiagonally.

%C Column 7 of A228482

%C Same recurrences as A228285 except in addition a smaller one for column 5

%H R. H. Hardin, <a href="/A228481/b228481.txt">Table of n, a(n) for n = 1..210</a>

%F a(n) = a(n-1) +85*a(n-2) +432*a(n-3) +192*a(n-4) -3711*a(n-5) -5096*a(n-6) +21164*a(n-7) +27340*a(n-8) -112654*a(n-9) -37244*a(n-10) +477721*a(n-11) -464722*a(n-12) -897815*a(n-13) +3102284*a(n-14) -4149918*a(n-15) +2761082*a(n-16) -138325*a(n-17) -1353257*a(n-18) +942033*a(n-19) +64683*a(n-20) -365483*a(n-21) +80904*a(n-22) +92350*a(n-23) -27097*a(n-24) -23292*a(n-25) +2585*a(n-26) +5635*a(n-27) +1405*a(n-28) -561*a(n-29) -545*a(n-30) -173*a(n-31) -14*a(n-32) +5*a(n-33) +a(n-34)

%e Some solutions for n=4

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Aug 22 2013

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Last modified April 23 11:06 EDT 2024. Contains 371905 sequences. (Running on oeis4.)