OFFSET
0,5
COMMENTS
Limit a(n+1)/a(n) = 1.465571... (as in Narayana's cows sequence A000930).
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (0,1,1,1).
FORMULA
MAPLE
a:= n-> (<<0|1|0|0>, <0|0|1|0>,
<0|0|0|1>, <1|1|1|0>>^n. <<0, 1, 1, 0>>)[1, 1]:
seq(a(n), n=0..50); # Alois P. Heinz, Oct 07 2016
MATHEMATICA
CoefficientList[Series[x*(1 + x - x^2)/(1 - x^2 - x^3 - x^4), {x, 0, 50}], x]
RecurrenceTable[{a[n] == a[n - 2] + a[n - 3] + a[n - 4], a[1] == 0, a[2] == a[3] == 1, a[4] == 0}, a, {n, 52}]
LinearRecurrence[{0, 1, 1, 1}, {0, 1, 1, 0}, 52]
PROG
(PARI) x='x+O('x^50); concat([0], Vec(x*(1+x-x^2)/(1-x^2-x^3-x^4))) \\ G. C. Greubel, May 02 2017
CROSSREFS
KEYWORD
nonn
AUTHOR
Nicolas Bègue, Oct 07 2016
EXTENSIONS
Corrected G.f. - G. C. Greubel, May 02 2017
STATUS
approved