A283421 Number of connected untraceable graphs on n vertices.

0, 0, 0, 1, 3, 21, 119, 1087, 12653, 233999, 6469055

Offset

1,5

Links

Table of n, a(n) for n=1..11.

Eric Weisstein's World of Mathematics, Connected Graph

Eric Weisstein's World of Mathematics, Untraceable Graph

Formula

a(n) = A001349(n) - A057864(n).

Crossrefs

Cf. A000088 (number of simple graphs on n vertices).

Cf. A001349 (number of simple connected graphs on n vertices).

Cf. A057864 (number of traceable simple graphs on n vertices).

Cf. A283420 (number of simple untraceable not necessarily connected graphs on n vertices).

Sequence in context: A178537 A084159 A046727 * A117512 A068127 A247247

Adjacent sequences: A283418 A283419 A283420 * A283422 A283423 A283424

Keyword

nonn,more

Author

Eric W. Weisstein, May 14 2017

Status

approved