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A278320 Number of nX3 0..1 arrays with rows and columns in lexicographic nondecreasing order but with exactly two mistakes.

%I A278320 #4 Nov 18 2016 06:38:30
%S A278320 0,20,236,1678,9714,51229,251892,1144205,4762445,18164685,63838081,
%T A278320 208288721,635843575,1829104046,4989647446,12978273537,32338548895,
%U A278320 77506161543,179299342255,401569610694,873025241923,1846627291485
%N A278320 Number of nX3 0..1 arrays with rows and columns in lexicographic nondecreasing order but with exactly two mistakes.
%C A278320 Column 3 of A278325.
%H A278320 R. H. Hardin, <a href="/A278320/b278320.txt">Table of n, a(n) for n = 1..210</a>
%F A278320 Empirical: a(n) = (1/25852016738884976640000)*n^23 + (1/102181884343418880000)*n^22 + (1/858671297003520000)*n^21 + (1259/14597412049059840000)*n^20 + (3617/810967336058880000)*n^19 + (1831/10670622842880000)*n^18 + (13746263/2688996956405760000)*n^17 + (19040863/158176291553280000)*n^16 + (101471197/45193226158080000)*n^15 + (1480973341/45193226158080000)*n^14 + (61001884543/165708495912960000)*n^13 + (3617038307/1158800670720000)*n^12 + (1537519018181/79088145776640000)*n^11 + (13469195909881/158176291553280000)*n^10 + (4270693429711/11298306539520000)*n^9 + (9457223412823/2824576634880000)*n^8 + (218151538495819/8002967132160000)*n^7 + (775352818331437/8002967132160000)*n^6 + (627425471079349/3478413818880000)*n^5 + (3995289195644399/14783258730240000)*n^4 + (6585215991983/43020065088000)*n^3 - (217394476291/586637251200)*n^2 - (1933447697/5354228880)*n
%e A278320 Some solutions for n=4
%e A278320 ..1..0..1. .1..1..0. .0..0..0. .0..0..1. .0..1..0. .1..0..1. .0..0..0
%e A278320 ..1..1..1. .0..1..0. .0..1..0. .1..0..0. .0..1..1. .1..0..1. .1..1..0
%e A278320 ..1..0..1. .0..1..1. .0..0..1. .1..1..1. .0..0..1. .1..0..0. .1..1..0
%e A278320 ..1..0..1. .1..1..1. .1..1..1. .0..0..1. .0..1..0. .1..1..1. .0..0..0
%Y A278320 Cf. A278325.
%K A278320 nonn
%O A278320 1,2
%A A278320 _R. H. Hardin_, Nov 18 2016