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A008238
a(n) = floor(n/4)*ceiling(n/4).
0
0, 0, 0, 0, 1, 2, 2, 2, 4, 6, 6, 6, 9, 12, 12, 12, 16, 20, 20, 20, 25, 30, 30, 30, 36, 42, 42, 42, 49, 56, 56, 56, 64, 72, 72, 72, 81, 90, 90, 90, 100, 110, 110, 110, 121, 132, 132, 132, 144, 156, 156, 156, 169, 182, 182
OFFSET
0,6
FORMULA
G.f.: x^4/((1-x)^3*(1+x)*(1+x^2)^2). - R. J. Mathar, Mar 11 2012
a(n) = floor(n/4)*floor((n+3)/4). - Bruno Berselli, Jun 08 2017
MATHEMATICA
f[n_]:=Module[{c=n/4}, Floor[c]Ceiling[c]]; f/@Range[0, 70] (* Harvey P. Dale, Apr 23 2011 *)
CROSSREFS
Cf. A002265.
Sequence in context: A170887 A103265 A341695 * A218870 A264869 A292728
KEYWORD
nonn,easy
STATUS
approved