A202567 - OEIS

%I #9 Oct 03 2025 09:41:16

%S 7343,56821,447963,3525903,27425677,213463753,1666015233,12999566073,

%T 101412911113,790978473677,6170149889927,48131634245907,

%U 375459360021267,2928810273128489,22846522525694475,178217379032743251

%N Number of (n+3)X4 binary arrays with no more than two of any consecutive four bits set in any row or column.

%C Column 1 of A202574

%H R. H. Hardin, <a href="/A202567/b202567.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 6*a(n-1) +17*a(n-2) -31*a(n-3) +142*a(n-4) -94*a(n-5) -4526*a(n-6) +2435*a(n-7) +5499*a(n-8) -3566*a(n-9) -284*a(n-10) +20671*a(n-11) -3473*a(n-12) -1834*a(n-13) +37405*a(n-14) +113249*a(n-15) -193747*a(n-16) -171282*a(n-17) +35862*a(n-18) -247228*a(n-19) -108314*a(n-20) +659634*a(n-21) -22532*a(n-22) +124304*a(n-23) +16148*a(n-24) -49068*a(n-25) -42800*a(n-26) -2728*a(n-27) -5440*a(n-28) +336*a(n-29)

%e Some solutions for n=2

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 21 2011