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%I #4 Nov 16 2016 07:04:47
%S 0,47,1541,46669,1443372,44653299,1380961734,42709293706,
%T 1320881956427,40851256530478,1263417354853348,39074034747765752,
%U 1208452761189472245,37374130557309864873,1155879385419493659726,35748180190801587747636
%N Number of nX3 0..3 arrays with every element plus 1 mod 4 equal to some element at offset (-1,-1) (-1,0) (-1,1) (0,-1) (0,1) (1,-1) or (1,0), with upper left element zero.
%C Column 3 of A278272.
%H R. H. Hardin, <a href="/A278268/b278268.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 36*a(n-1) -162*a(n-2) +228*a(n-3) -2482*a(n-4) +9972*a(n-5) -2070*a(n-6) +69586*a(n-7) -484397*a(n-8) +418362*a(n-9) -1615409*a(n-10) +16222445*a(n-11) -13260202*a(n-12) -86384152*a(n-13) +117435510*a(n-14) -54031926*a(n-15) +284670365*a(n-16) -3119976438*a(n-17) +20033186387*a(n-18) -26598585251*a(n-19) -52565516946*a(n-20) +106882788758*a(n-21) -76901072309*a(n-22) +323946214918*a(n-23) -469487165715*a(n-24) +290049469568*a(n-25) -683336099985*a(n-26) +523472975365*a(n-27) -100966982130*a(n-28) +168294869288*a(n-29) -106410454776*a(n-30) -67944547904*a(n-31) -12083149152*a(n-32) +13561255808*a(n-33) +23565683520*a(n-34) +7666456192*a(n-35) +1394460416*a(n-36) -327828480*a(n-37) -226152448*a(n-38) +42903552*a(n-39) +8224768*a(n-40)
%e Some solutions for n=4
%e ..0..1..0. .0..0..1. .0..1..0. .0..2..2. .0..1..1. .0..1..1. .0..1..1
%e ..3..2..0. .1..2..0. .1..2..3. .1..3..1. .1..2..2. .0..2..1. .3..2..1
%e ..2..3..2. .0..3..3. .0..3..1. .0..1..1. .1..3..3. .1..3..1. .2..0..2
%e ..1..2..1. .1..2..2. .3..0..3. .3..2..0. .0..0..2. .0..3..2. .3..3..1
%Y Cf. A278272.
%K nonn
%O 1,2
%A _R. H. Hardin_, Nov 16 2016
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