OFFSET
1,3
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 1..1000
S. Mertens, Small random instances of the stable roommates problem, arXiv preprint arXiv:1502.06635 [math.CO], 2015.
MAPLE
with(combinat): seq(numbpart(2*n)-numbpart(2*n-2)-numbpart(n), n=1..45); # Muniru A Asiru, Oct 10 2018
MATHEMATICA
a[n_] := PartitionsP[2n] - PartitionsP[2n - 2] - PartitionsP[n];
Array[a, 44] (* Jean-François Alcover, Oct 10 2018 *)
PROG
(PARI) vector(100, n, numbpart(2*n)-numbpart(2*n-2)-numbpart(n)) \\ Altug Alkan, Nov 11 2015
(Haskell)
a263847 n = a263847_list !! (n-1)
a263847_list = 0 : zipWith (-)
(zipWith (-) (tail qs) qs) (drop 2 a000041_list)
where qs = es $ tail a000041_list
es [] = []; es [x] = []; es (_:x:xs) = x : es xs
-- Reinhard Zumkeller, Nov 12 2015
(GAP) List([1..45], n->NrPartitions(2*n)-NrPartitions(2*n-2)-NrPartitions(n)); # Muniru A Asiru, Oct 10 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Nov 11 2015
STATUS
approved