A070052 Number of Bottleneck-Monge matrices with 4 rows.

16, 87, 384, 1516, 5535, 19030, 62347, 196301, 597725, 1768733, 5105853, 14423037, 39968765, 108884733, 292116989, 772923389, 2019573757, 5216813053, 13334904829, 33758183421, 84702265341, 210777210877, 520498839549, 1276178857981, 3108165910525, 7522859614205, 18101546516477

Offset

1,1

Comments

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]).

Links

Nathaniel Johnston, Table of n, a(n) for n = 1..400

Formula

a(N) = a(4, N), where a(P, N) is defined recursively in A070050.

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

Crossrefs

Cf. A070050, A070051, A070053, A070054, A070055, A070056, A070057.

Sequence in context: A224143 A225007 A352953 * A203249 A022676 A035291

Adjacent sequences: A070049 A070050 A070051 * A070053 A070054 A070055

Keyword

nonn,easy

Author

Pascal Prea (pascal.prea(AT)lim.univ-mrs.fr), Apr 18 2002

Extensions

a(10) - a(27) from Nathaniel Johnston, Apr 13 2011

Status

approved