login
A342284
Number of friendly 3-watermelons of length n.
1
1, 0, 2, 6, 24, 110, 550, 2922, 16242, 93520, 553980, 3359384, 20777588, 130696662, 834244830, 5393850898, 35272830054, 233016356788, 1553427829684, 10441803227652, 70715551631992, 482201548554776, 3308810614160224, 22836540660981088, 158458108961055864
OFFSET
0,3
REFERENCES
Essam, J.W. and Guttmann, A.J., 1995. Vicious walkers and directed polymer networks in general dimensions. Physical Review E, 52(6), pp. 5849ff. See (63).
Iwan Jensen, Three friendly walkers, Journal of Physics A: Mathematical and Theoretical, Volume 50:2 (2017), #24003, 14 pages; https://doi.org/10.1088/1751-8121/50/2/024003. See F_3(x).
FORMULA
G.f. = 1 - 2*x + G(x), where G(x) = 2*x+2*x^2+6*x^3+24*x^4+110*x^5+550*x^6+... is the g.f. for A342282.
CROSSREFS
Sequence in context: A372527 A138020 A046646 * A174195 A274378 A177521
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Mar 19 2021
STATUS
approved