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A208876 Number of 5Xn 0..3 arrays with new values 0..3 introduced in row major order and no element equal to more than one of its immediate leftward or upward or right-upward antidiagonal neighbors.

%I A208876 #7 Jul 22 2025 21:33:17
%S A208876 51,28246,16205218,9130195864,5134914951163,2887736845657700,
%T A208876 1624001903270517563,913306247364608338853,513625349165806029159816,
%U A208876 288852734835443348518960257,162445063843968446617446229944
%N A208876 Number of 5Xn 0..3 arrays with new values 0..3 introduced in row major order and no element equal to more than one of its immediate leftward or upward or right-upward antidiagonal neighbors.
%C A208876 Row 5 of A208872
%H A208876 R. H. Hardin, <a href="/A208876/b208876.txt">Table of n, a(n) for n = 1..202</a>
%F A208876 Empirical: a(n) = 835*a(n-1) -183323*a(n-2) +18547299*a(n-3) -987322450*a(n-4) +26936215656*a(n-5) -259592930108*a(n-6) -3698904511972*a(n-7) +105056981064194*a(n-8) -468082290224790*a(n-9) -8220453963894770*a(n-10) +93015305289328522*a(n-11) -3009215708038944*a(n-12) -4338208630525451740*a(n-13) +17757865170412343388*a(n-14) +59736218122280906604*a(n-15) -622267506833186033977*a(n-16) +938869955167775461259*a(n-17) +8000262558220637738773*a(n-18) -56634053288703764393173*a(n-19) +209139140116278936305898*a(n-20) -546065890364575413337540*a(n-21) +1008121942435233118210008*a(n-22) -1160912061971582376908448*a(n-23) +524709510887340807606720*a(n-24) +511243927003064543493888*a(n-25) -896720906468773868608512*a(n-26) +430645964613584885342208*a(n-27) +74415201590159365275648*a(n-28) -159217853403663932719104*a(n-29) +60721875388690274451456*a(n-30) -7836898836947747733504*a(n-31) for n>34
%e A208876 Some solutions for n=4
%e A208876 ..0..0..1..0....0..1..0..2....0..0..0..0....0..0..0..1....0..0..0..1
%e A208876 ..2..3..1..0....0..3..3..0....1..2..2..1....2..3..2..0....1..1..2..1
%e A208876 ..0..1..2..1....1..0..2..1....1..0..1..2....1..2..1..1....0..1..0..2
%e A208876 ..1..2..3..3....1..2..1..2....2..2..1..0....1..0..2..1....2..1..0..3
%e A208876 ..0..3..0..0....0..2..0..3....0..3..0..1....3..3..1..2....1..0..1..0
%K A208876 nonn
%O A208876 1,1
%A A208876 _R. H. Hardin_ Mar 02 2012