A070051 Number of Bottleneck-Monge matrices with 3 rows. In the formula below, P=3.

8, 33, 117, 384, 1194, 3558, 10238, 28606, 77950, 207870, 543998, 1400318, 3552254, 8894462, 22011902, 53903358, 130744318, 314376190, 749928446, 1775894526, 4177264638, 9764863998, 22695378942, 52466548734, 120686903294, 276320747518, 629900574718

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

Empirical G.f.: -x*(32*x^5-140*x^4+213*x^3-154*x^2+55*x-8) / ((x-1)*(2*x-1)^5). - Colin Barker, Feb 28 2013

Crossrefs

Cf. A070050, A070052, A070053, A070054, A070055, A070056, A070057.

Sequence in context: A051836 A278670 A301771 * A087235 A222346 A317017

Adjacent sequences: A070048 A070049 A070050 * A070052 A070053 A070054

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