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 A234699 Number of (n+1)X(3+1) 0..7 arrays with every 2X2 subblock having its diagonal sum differing from its antidiagonal sum by 5 (constant stress 1X1 tilings) 1

%I

%S 16848,74308,329984,1558600,7424496,37338544,189345872,1006857472,

%T 5389971408,30077051488,168561386384,979772704480,5704468149456,

%U 34304416485664,206090647457552,1274575646527072,7855291807049808

%N Number of (n+1)X(3+1) 0..7 arrays with every 2X2 subblock having its diagonal sum differing from its antidiagonal sum by 5 (constant stress 1X1 tilings)

%C Column 3 of A234702

%H R. H. Hardin, <a href="/A234699/b234699.txt">Table of n, a(n) for n = 1..186</a>

%F Empirical: a(n) = 20*a(n-1) +141*a(n-2) -5340*a(n-3) +5451*a(n-4) +616740*a(n-5) -2678805*a(n-6) -39706740*a(n-7) +278440182*a(n-8) +1491646680*a(n-9) -16092380232*a(n-10) -27470360160*a(n-11) +601403119168*a(n-12) -194332088960*a(n-13) -15257818574160*a(n-14) +26729605928640*a(n-15) +263906583339744*a(n-16) -801813357648000*a(n-17) -2982678610973184*a(n-18) +13948745101747200*a(n-19) +18588639920403456*a(n-20) -156794289434542080*a(n-21) -1681574850293760*a(n-22) +1140373919202508800*a(n-23) -1022866437252096000*a(n-24) -5015897891205120000*a(n-25) +8536532135362560000*a(n-26) +10656426280550400000*a(n-27) -31534442652303360000*a(n-28) +815374290124800000*a(n-29) +46191901645209600000*a(n-30) -31856483893248000000*a(n-31)

%e Some solutions for n=2

%e ..7..1..6..5....5..5..5..0....6..5..6..5....6..0..3..2....5..0..3..3

%e ..2..1..1..5....7..2..7..7....2..6..2..6....5..4..2..6....7..7..5..0

%e ..3..7..2..1....1..1..1..6....3..2..3..2....7..1..4..3....6..1..4..4

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 29 2013

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Last modified May 28 09:09 EDT 2022. Contains 354112 sequences. (Running on oeis4.)