A054932 Number of unlabeled connected digraphs up to complementarity.

1, 1, 7, 95, 4628, 760731, 439476534, 895794710762, 6512183359880844, 170617184427498641390, 16261113406024864291983616, 5683340191820651519596089554647, 7334531479545984537334675978032833750, 35157813638509073199087893774184443496308877

Offset

1,3

Links

Andrew Howroyd, Table of n, a(n) for n = 1..50

V. A. Liskovets, Some easily derivable sequences, J. Integer Sequences, 3 (2000), #00.2.2.

Formula

a(n) = A003085(n) - (A000273(n)-A003086(n))/2. - Andrew Howroyd, Sep 17 2018

Maple

A054932 := proc(n)
    A003085(n)-(A000273(n)-A003086(n))/2 ;
end proc:
seq(A054932(n), n=1..13) ; # R. J. Mathar, Mar 04 2018

Mathematica

A000273 = Cases[Import["https://oeis.org/A000273/b000273.txt", "Table"], {_, _}][[All, 2]];
A003085 = Cases[Import["https://oeis.org/A003085/b003085.txt", "Table"], {_, _}][[All, 2]];
A003086 = Cases[Import["https://oeis.org/A003086/b003086.txt", "Table"], {_, _}][[All, 2]];
a[n_] := A003085[[n]] - (A000273[[n + 1]] - A003086[[n]])/2;
Array[a, 50] (* Jean-François Alcover, Sep 01 2019 *)

Crossrefs

Cf. A000273, A003085, A003086, A054931.

Sequence in context: A130183 A156961 A239999 * A217240 A222834 A327676

Adjacent sequences: A054929 A054930 A054931 * A054933 A054934 A054935

Keyword

nonn,easy

Author

N. J. A. Sloane, May 24 2000

Extensions

Terms a(14) and beyond from Andrew Howroyd, Sep 17 2018

Status

approved