A039648 Number of n-step self-avoiding paths on the first octant of a 3-dimensional cubic lattice, starting at the origin.

1, 3, 9, 33, 123, 489, 1947, 7977, 32817, 137253, 576993, 2452071, 10468245, 45032733, 194475321, 844608567, 3680153043, 16105438515, 70677344403, 311242931097, 1373860647453, 6081635195553

Offset

0,2

Links

Table of n, a(n) for n=0..21.

Crossrefs

Cf. A039618, A005566.

Sequence in context: A148997 A082841 A151038 * A307454 A219261 A182530

Adjacent sequences: A039645 A039646 A039647 * A039649 A039650 A039651

Keyword

nonn,walk,more

Author

David W. Wilson

Extensions

a(19)-a(21) from Scott R. Shannon, Aug 14 2020

Title clarified by Sean A. Irvine, Feb 20 2021

Status

approved