A218093 - OEIS

%I #7 Mar 12 2015 17:02:41

%S 13,106,1105,12075,141533,1812216,25188019,378725365,6135529675,

%T 106586385708,1976799958367,38978490654831,814024466784025,

%U 17943457752971680,416183933276776375,10128962147830237953,258021086313431979827,6863916836407264864380

%N Number of transitive reflexive early confluent binary relations R on n labeled elements with max_{x}(|{y : xRy}|) = 3.

%C R is early confluent iff (xRy and xRz) implies (yRz or zRy) for all x, y, z.

%D A. P. Heinz (1990). Analyse der Grenzen und Möglichkeiten schneller Tableauoptimierung. PhD Thesis, Albert-Ludwigs-Universität Freiburg, Freiburg i. Br., Germany.

%H Alois P. Heinz, <a href="/A218093/b218093.txt">Table of n, a(n) for n = 3..200</a>

%F E.g.f.: exp(x*exp(x*exp(x)+x^2/2)+x^2/2*exp(x)+x^3/6)-exp(x*exp(x)+x^2/2).

%F a(n) = A210911(n) - A135312(n).

%p egf:= exp(x*exp(x*exp(x)+x^2/2)+x^2/2*exp(x)+x^3/6)-exp(x*exp(x)+x^2/2):

%p a:= n-> n!* coeff(series(egf, x, n+1), x, n):

%p seq(a(n), n=3..30);

%Y Column k=3 of A135313.

%K nonn

%O 3,1

%A _Alois P. Heinz_, Oct 20 2012