A187237 Number of simple connected imperfect graphs on n vertices.

0, 0, 0, 0, 1, 7, 129, 3312, 134303, 8594350, 894307856, 158323596832

Offset

1,6

Links

Table of n, a(n) for n=1..12.

Eric Weisstein's World of Mathematics, Imperfect Graph.

Formula

a(n) = A001349(n) - A052433(n).

Crossrefs

Cf. A001349, A052433, A187236.

Sequence in context: A263686 A002614 A333561 * A095885 A361369 A361367

Adjacent sequences: A187234 A187235 A187236 * A187238 A187239 A187240

Keyword

nonn,more,hard

Author

Eric W. Weisstein, Mar 07 2011

Extensions

a(12) using formula by Falk Hüffner, Jan 15 2016

Status

approved