OFFSET
0,8
COMMENTS
a(n) > 0 for all n >= 5.
FORMULA
a(n) ~ exp(Pi*sqrt(2*n/3)) / (4*n*sqrt(3)) * (1 - (sqrt(3/2)/Pi + 73*Pi/(24*sqrt(6)))/sqrt(n) + (73/16 + 3025*Pi^2/6912)/n). - Vaclav Kotesovec, Sep 03 2019
G.f.: (q^2+q-1)/Product_{n>=1} (1-q^n). - Shouvik Datta, Sep 07 2019
MATHEMATICA
Table[-(PartitionsP[n] - PartitionsP[n - 1] - PartitionsP[n - 2]), {n, 0, 20}] (* Shouvik Datta, Sep 07 2019 *)
PROG
(PARI) a(n) = numbpart(n-2) + numbpart(n-1) - numbpart(n); \\ Michel Marcus, Sep 03 2019
CROSSREFS
KEYWORD
easy,sign
AUTHOR
Max Alekseyev, Sep 03 2019
STATUS
approved