A260775 Certain directed lattice paths.

1, 4, 28, 264, 2860, 33592, 416024, 5348880, 70715340, 955277400, 13128240840, 182965127280, 2579808294648, 36734706144304, 527495903500720, 7629973004184608, 111068129754096396, 1625888084299461528, 23919596771720906984, 353467725574013402800

Offset

0,2

Comments

See Dziemianczuk (2014) for precise definition.

Links

Lars Blomberg, Table of n, a(n) for n = 0..100

M. Dziemianczuk, On Directed Lattice Paths With Additional Vertical Steps, arXiv preprint arXiv:1410.5747 [math.CO], 2014.

Maciej Dziemiańczuk, On directed lattice paths with vertical steps, Discrete Math., 339 (2016), 1116-1139.

Alex Hall, OEIS explorer

Formula

See Dziemianczuk (2014) Equation (36b) with N=2.

a(n) = 2 * A000108(2*n) for n > 0. [Agrees with the reference, found using OEIS explorer.] - Andrey Zabolotskiy, May 08 2021

Crossrefs

Cf. A000108, A260769, A260770, A260771, A260772, A260773, A260774, A260776.

Sequence in context: A177403 A360775 A196523 * A292810 A368892 A360727

Adjacent sequences: A260772 A260773 A260774 * A260776 A260777 A260778

Keyword

nonn,easy

Author

N. J. A. Sloane, Jul 30 2015

Extensions

More terms from Lars Blomberg, Aug 01 2015

Status

approved