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 A213769 Principal diagonal of the convolution array A213768. 3

%I

%S 1,8,26,63,136,272,521,968,1762,3159,5600,9840,17169,29784,51418,

%T 88399,151432,258592,440345,747960,1267586,2143783,3618816,6098208,

%U 10260001,17236712,28918106,48454623,81093832,135569264,226404905

%N Principal diagonal of the convolution array A213768.

%H Clark Kimberling, <a href="/A213769/b213769.txt">Table of n, a(n) for n = 1..1000</a>

%H <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (4,-4,-2,4,0,-1).

%F a(n) = 4*a(n-1) - 4*a(n-2) - 2*a(n-3) + 4*a(n-4) - a(n-6).

%F G.f.: f(x)/g(x), where f(x) = x*(1 + 4*x - 2*x^2 - 7*x^3) and g(x) = (1 - 2*x + x^3 )^2.

%t (See A213768.)

%t LinearRecurrence[{4,-4,-2,4,0,-1},{1,8,26,63,136,272},40] (* _Harvey P. Dale_, Jan 08 2015 *)

%Y Cf. A213768, A213500.

%K nonn,easy

%O 1,2

%A _Clark Kimberling_, Jun 21 2012

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Last modified December 14 12:04 EST 2019. Contains 329979 sequences. (Running on oeis4.)