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A173809 a(2n+1) = 1+A131941(2n+1). a(2n) = A131941(2n).

%I A173809 #10 Aug 10 2021 18:26:40
%S A173809 2,3,9,16,30,47,73,104,146,195,257,328,414,511,625,752,898,1059,1241,
%T A173809 1440,1662,1903,2169,2456,2770,3107,3473,3864,4286,4735,5217,5728,
%U A173809 6274,6851,7465,8112,8798,9519,10281,11080
%N A173809 a(2n+1) = 1+A131941(2n+1). a(2n) = A131941(2n).
%C A173809 An array T(n,k) of a(n) and its successive differences is T(1,k) = a(k), T(n,k) = T(n-1,k+1)-T(n-1,k) and starts:
%C A173809 2, 3, 9, 16, 30, 47, 73, 104, 146, 195, 257, 328,...
%C A173809 1, 6, 7, 14, 17, 26, 31, 42, 49, 62, 71, 86, 97, 114,... interleaved A056220 and A051890
%C A173809 5, 1, 7, 3, 9, 5, 11, 7, 13, 9, 15, 11, 17, 13, 19, 15.... A158552
%C A173809 -4, 6, -4, 6, -4, 6, -4, 6, -4, 6, -4, 6, -4, 6, -4,... A010711
%C A173809 10, -10, 10, -10, 10, -10, 10, -10, 10, -10, 10,..
%H A173809 <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (3,-2,-2,3,-1).
%F A173809 G.f.: -x*(-2+3*x+x^3-4*x^2) / ( (1+x)*(x-1)^4 ). - R. J. Mathar, Jan 13 2011
%F A173809 a(2n) = A172482(n-1).
%F A173809 a(n)+a(n+1) = A116731(n+2). - R. J. Mathar, Jan 13 2011
%t A173809 LinearRecurrence[{3,-2,-2,3,-1},{2,3,9,16,30},60] (* _Harvey P. Dale_, Aug 10 2021 *)
%K A173809 nonn,easy
%O A173809 1,1
%A A173809 _Paul Curtz_, Feb 25 2010