cp's OEIS Frontend

A128999 Start with an integer (in this case 1). First, add 5 or 6 if the integer is odd or even, respectively. Then divide by 2.

%I A128999 #22 Aug 29 2024 02:39:09
%S A128999 1,3,4,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
%T A128999 5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
%U A128999 5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5
%N A128999 Start with an integer (in this case 1). First, add 5 or 6 if the integer is odd or even, respectively. Then divide by 2.
%C A128999 Note that any a(1) <= 5 converges to 5 and any a(1) >= 6 converges to 6.
%C A128999 Decimal expansion of 1211/900. - _Elmo R. Oliveira_, May 05 2024
%H A128999 Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/RecursiveSequences.html#arithmprog">Arithmetic Progression</a>.
%H A128999 <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (1).
%F A128999 a(n) = [a(n-1) + b]/d, if a(n) even = [a(n-1) + c]/d, if a(n) odd (starting a(1)=1 with b=5, c=6, d=2).
%F A128999 a(n) = 5 for n >= 4. - _R. J. Mathar_, Oct 31 2007
%F A128999 G.f.: x*(1+2*x+x^2+x^3)/(1-x). - _Elmo R. Oliveira_, May 05 2024
%t A128999 PadRight[{1, 3, 4}, 100, 5] (* _Paolo Xausa_, Aug 28 2024 *)
%Y A128999 Cf. A085600.
%K A128999 easy,nonn
%O A128999 1,2
%A A128999 Adam F. Schwartz (adam_s(AT)mit.edu), May 01 2007
%E A128999 More terms from _R. J. Mathar_, Oct 31 2007