1,1
Column 3 of A183912.
R. H. Hardin, Table of n, a(n) for n = 1..199
Empirical: a(n) = (1/6)*n^3 + 2*n^2 + (5/6)*n - 8 for n>2.
Conjectures from Colin Barker, Apr 05 2018: (Start)
G.f.: x*(2 - 3*x + 9*x^2 - 8*x^3 - x^4 + 2*x^5) / (1 - x)^4.
a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4) for n>6.
(End)
All solutions for n=2:
..1....0....0....0....1
..1....0....0....2....2
..2....0....2....2....3
..3....0....2....2....3
Cf. A183912.
Sequence in context: A127436 A064168 A118727 * A042361 A114300 A099207
Adjacent sequences: A183903 A183904 A183905 * A183907 A183908 A183909
nonn
R. H. Hardin, Jan 07 2011
approved