A290866 a(n) = number of segments (edges) in the configuration A290447(n).

0, 1, 3, 8, 20, 45, 91, 168, 285, 450, 670, 981, 1375, 1902, 2568, 3371, 4326, 5522, 6927, 8639, 10624, 12882, 15489, 18559, 22006, 25904, 30321, 35254, 40728, 46959, 53721, 61354, 69734, 78917, 89029, 100018, 111758, 124759, 138943

Offset

1,3

Comments

Only edges above the line are counted. Total edges = a(n) + n - 1.

Links

David Applegate, Table of n, a(n) for n = 1..100

Formula

a(n) = A290447(n) + A290865(n).

Crossrefs

Cf. A290447, A290865, A290867.

Sequence in context: A192982 A096585 A057765 * A014628 A134393 A034504

Adjacent sequences: A290863 A290864 A290865 * A290867 A290868 A290869

Keyword

nonn

Author

David Applegate, Aug 12 2017

Status

approved