1,2

R. W. Robinson, Counting labeled acyclic digraphs, pp. 239-273 of F. Harary, editor, New Directions in the Theory of Graphs. Academic Press, NY, 1973.

V. Jovovic, G. Kilibarda, Enumeration of labeled initially-finally connected digraphs, Scientific review, Serbian Scientific Society, 19-20 (1996), 237-247.

Sequence in context: A007654 A001080 A099852 this_sequence A049524 A033493 A094045

Adjacent sequences: A003026 A003027 A003028 this_sequence A003030 A003031 A003032

nonn,nice,easy

njas

Corrected and extended by Vladeta Jovovic, Goran Kilibarda (vladeta(AT)Eunet.yu)