%I #10 Jun 13 2015 00:49:05
%S 1,0,1,1,1,1,3,1,3,3,3,3,6,3,6,6,6,6,10,6,10,10,10,10,15,10,15,15,15,
%T 15,21,15,21,21,21,21,28,21,28,28,28,28,36,28,36,36,36,36,45,36,45,45,
%U 45,45,55,45,55,55,55,55,66
%N Expansion of 1/((1-x^2)(1-x^3)(1-x^6)).
%H <a href="/index/Rec#order_11">Index entries for linear recurrences with constant coefficients</a>, signature (0,1,1,0,-1,1,0,-1,-1,0,1).
%F a(6n) = a(6n+2) = a(6n+3) = a(6n+4) = a(6n+5) = n*(n+1)/2. a(6n+1) = (n-1)*n/2. - _Franklin T. Adams-Watters_, Oct 27 2014
%o (PARI) a(n)=(n^2+(4*((n+2)%3)+7+3*(-1)^n)*n+57+33*(-1)^n/2)\72 \\ _Tani Akinari_, Oct 27 2014
%Y Cf. A024163.
%K nonn,easy
%O 0,7
%A _N. J. A. Sloane_.
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