A037605 - OEIS

%I #13 Oct 16 2024 16:38:36

%S 1,7,38,191,957,4788,23941,119707,598538,2992691,14963457,74817288,

%T 374086441,1870432207,9352161038,46760805191,233804025957,

%U 1169020129788,5845100648941,29225503244707,146127516223538,730637581117691

%N Base 5 digits are, in order, the first n terms of the periodic sequence with initial period 1,2,3.

%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (5,0,1,-5).

%H <a href="/index/Ar#5-automatic">Index entries for 5-automatic sequences</a>.

%F G.f.: x*(1+2*x+3*x^2) / ( (x-1)*(5*x-1)*(1+x+x^2) ). - _R. J. Mathar_, Apr 27 2015

%F A007091(a(n)) = A037610(n). - _R. J. Mathar_, Apr 27 2015

%t Table[FromDigits[PadRight[{},n,{1,2,3}],5],{n,30}] (* or *) LinearRecurrence[{5,0,1,-5},{1,7,38,191},30] (* _Harvey P. Dale_, Oct 16 2024 *)

%o (PARI) a(n)=([0,1,0,0; 0,0,1,0; 0,0,0,1; -5,1,0,5]^(n-1)*[1;7;38;191])[1,1] \\ _Charles R Greathouse IV_, Feb 13 2017

%K nonn,base,easy

%O 1,2

%A _Clark Kimberling_