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%I #8 Jul 31 2015 12:53:36
%S 1,1,2,3,4,5,8,9,13,16,22,26,37,43,60,71,98,115,160,187,259,304,420,
%T 492,681,797,1102,1291,1784,2089,2888,3381,4673,5472,7562,8854,12237,
%U 14327,19800,23183,32038,37511,51840,60695,83879,98208,135720,158904,219601
%N a(n) = sum along n-th diagonal of A094102 (sloping downward to left).
%H Harvey P. Dale, <a href="/A094103/b094103.txt">Table of n, a(n) for n = 1..1000</a>
%H <a href="/index/Rec#order_07">Index entries for linear recurrences with constant coefficients</a>, signature (0, 1, 1, 1, -1, 0, -1).
%F G.f.: (1+x+x^2+x^3) / [(1-x^3)(1-x^2-x^4)].
%F a(1)=1, a(2)=1, a(3)=2, a(4)=3, a(5)=4, a(6)=5, a(7)=8, a(n)=a(n-2)+ a(n-3)+a(n-4)-a(n-5)-a(n-7) [From Harvey P. Dale, Oct 09 2011]
%e a(8) = 2+3+2+1+1 = 9.
%t CoefficientList[Series[(1+x+x^2+x^3)/((1-x^3)(1-x^2-x^4)),{x,0,60}],x] (* or *) LinearRecurrence[{0,1,1,1,-1,0,-1},{1,1,2,3,4,5,8},61] (* _Harvey P. Dale_, Oct 09 2011 *)
%K nonn,easy
%O 1,3
%A Alysia Veenhof (ladyluck1899(AT)hotmail.com), May 05 2004
%E More terms from Pab Ter (pabrlos(AT)yahoo.com), May 24 2004
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