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 A172678 Number of 4*n X n 0..2 arrays with row sums 2 and column sums 8 1

%I #13 Jan 17 2018 03:46:25

%S 1,1107,57775905,40629560387130,203571289613781911250,

%T 4937928427617947420104982250,447362835296127429187676764430583750,

%U 125661678519106774927206307245894357500775000

%N Number of 4*n X n 0..2 arrays with row sums 2 and column sums 8

%H R. H. Hardin, <a href="/A172678/b172678.txt">Table of n, a(n) for n=1..24</a>

%F a(n) = (1/(8!)^n)*Sum_(v=0..n} Sum_{m=0..n-v} Sum_{g=0..n-v-m} Sum_{b=0..n-v-m-g} (28^b*210^g*420^m*105^v*n!(4n)!(8n-2b-4g-6m-8v)!)/((n-b-g-m-v)!b!g!m!v!(4n-b-2g-3m-4v)!2^(4n-b-2g-3m-4v)). - _Shanzhen Gao_, Feb 25 2010

%K nonn

%O 1,2

%A _R. H. Hardin_, Feb 06 2010

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Last modified September 25 12:35 EDT 2023. Contains 365644 sequences. (Running on oeis4.)