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%I #8 Feb 28 2013 09:03:33
%S 16,87,384,1516,5535,19030,62347,196301,597725,1768733,5105853,
%T 14423037,39968765,108884733,292116989,772923389,2019573757,
%U 5216813053,13334904829,33758183421,84702265341,210777210877,520498839549,1276178857981,3108165910525,7522859614205,18101546516477
%N Number of Bottleneck-Monge matrices with 4 rows.
%C Bottleneck-Monge matrices are {0,1} matrices A in which, for every i<j and k<l, max(A[i,l],A[j,k]) <= max(A[i,k],A[j,l]).
%H Nathaniel Johnston, <a href="/A070052/b070052.txt">Table of n, a(n) for n = 1..400</a>
%F a(N) = a(4, N), where a(P, N) is defined recursively in A070050.
%F Empirical G.f.: -x*(128*x^7-799*x^6+1835*x^5-2199*x^4+1542*x^3-647*x^2+153*x-16) / ((x-1)*(2*x-1)^7). - _Colin Barker_, Feb 28 2013
%Y Cf. A070050, A070051, A070053, A070054, A070055, A070056, A070057.
%K nonn,easy
%O 1,1
%A Pascal Prea (pascal.prea(AT)lim.univ-mrs.fr), Apr 18 2002
%E a(10) - a(27) from _Nathaniel Johnston_, Apr 13 2011
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