cp's OEIS Frontend

A194350 Numbers covering A000027: a(n) = (1, 1, 2, 5) * A011557(n).

%I A194350 #27 Feb 18 2025 08:59:29
%S A194350 1,1,2,5,10,10,20,50,100,100,200,500,1000,1000,2000,5000,10000,10000,
%T A194350 20000,50000,100000,100000,200000,500000,1000000,1000000,2000000,
%U A194350 5000000,10000000,10000000,20000000,50000000
%N A194350 Numbers covering A000027: a(n) = (1, 1, 2, 5) * A011557(n).
%C A194350 3=1+2, 4=1+1+2, 6=1+5, 7=2+5, 8=1+2+5, 9=1+1+2+5, 11=1+10, 12=2+10, 13=1+2+10.
%C A194350 a(n) is used only once. Like weights.
%H A194350 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,0,10).
%F A194350 From _Colin Barker_, Jan 25 2012: (Start)
%F A194350 a(1)=1, a(2)=1, a(3)=2, a(4)=5, a(n)=10*a(n-4).
%F A194350 G.f.: x*(1+x+2*x^2+5*x^3)/(1-10*x^4). (End)
%t A194350 LinearRecurrence[{0,0,0,10},{1,1,2,5},40] (* _Harvey P. Dale_, Jan 21 2019 *)
%o A194350 (PARI) a(n)=10^(n\4)*[1/2,1,1,2][n%4+1] \\ _Charles R Greathouse IV_, Dec 21 2011
%Y A194350 Cf. A000027, A011557.
%K A194350 nonn,easy
%O A194350 1,3
%A A194350 _Paul Curtz_, Aug 22 2011