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A026970 a(n) = Sum_{k=0..n} (k+1) * A026637(n,k). 0

%I #12 Oct 20 2019 16:23:00

%S 1,3,8,25,60,147,336,765,1700,3751,8184,17745,38220,81915,174752,

%T 371365,786420,1660239,3495240,7340025,15379100,32156323,67108848,

%U 139810125,290805060,603979767,1252698776,2594876065,5368709100

%N a(n) = Sum_{k=0..n} (k+1) * A026637(n,k).

%F Conjectures from _Colin Barker_, Feb 18 2016: (Start)

%F a(n) = -((-1)^n-2^(n+2)+3)*(n+2)/6 for n>0.

%F a(n) = 4*a(n-1)-2*a(n-2)-8*a(n-3)+7*a(n-4)+4*a(n-5)-4*a(n-6) for n>6.

%F G.f.: (1-x-2*x^2+7*x^3-7*x^4-4*x^5+4*x^6) / ((1-x)^2*(1+x)^2*(1-2*x)^2).

%F (End)

%K nonn

%O 0,2

%A _Clark Kimberling_

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Last modified April 25 11:36 EDT 2024. Contains 371968 sequences. (Running on oeis4.)