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%I #4 Mar 12 2016 08:44:16
%S 1176,4126368,5750902944,6697695002208,7142783643783792,
%T 7232246139319438944,7076007579749239522560,6756572506861579320074976,
%U 6335222052939240175011338736,5856894219696861529450357235808
%N Number of nX4 0..7 arrays with some element plus some horizontally, diagonally, antidiagonally or vertically adjacent neighbor totalling seven exactly once.
%C Column 4 of A270150.
%H R. H. Hardin, <a href="/A270147/b270147.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 1742*a(n-1) -827249*a(n-2) +55735166*a(n-3) +2410177430*a(n-4) -208388398056*a(n-5) -3167015848153*a(n-6) +256479806611406*a(n-7) +2376722394136390*a(n-8) -119974226647646126*a(n-9) -748066037036869804*a(n-10) +14495677890626797680*a(n-11) -44282335922464026472*a(n-12) -87656882172897101898*a(n-13) +633122185223835748191*a(n-14) -486595208994066512314*a(n-15) -2521515704709696475982*a(n-16) +4786585967458397581320*a(n-17) +2256779180091586437315*a(n-18) -11568026205666473386010*a(n-19) +4081366110373471964624*a(n-20) +11206797106037834726810*a(n-21) -8694022358907130403200*a(n-22) -3768022188795704598344*a(n-23) +5316074296028246592431*a(n-24) -410670862474703529840*a(n-25) -1029555514715631146860*a(n-26) +336961514541159804000*a(n-27) -22395037969800912100*a(n-28) -1605006621279476000*a(n-29) -20684134872040000*a(n-30) for n>31
%e Some solutions for n=1
%e ..5..7..6..1. .4..4..5..2. .7..5..2..3. .1..5..2..4. .6..0..0..7
%Y Cf. A270150.
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 12 2016
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