cp's OEIS Frontend

A319702 Filter sequence for sequences that are constant for all even terms >= 2.

%I A319702 #12 Apr 07 2023 11:27:27
%S A319702 1,2,3,2,4,2,5,2,6,2,7,2,8,2,9,2,10,2,11,2,12,2,13,2,14,2,15,2,16,2,
%T A319702 17,2,18,2,19,2,20,2,21,2,22,2,23,2,24,2,25,2,26,2,27,2,28,2,29,2,30,
%U A319702 2,31,2,32,2,33,2,34,2,35,2,36,2,37,2,38,2,39,2,40,2,41,2,42,2,43,2,44,2,45,2,46,2,47,2,48,2,49,2,50,2,51,2,52,2,53,2,54,2,55,2,56,2,57,2,58,2,59,2,60,2,61,2
%N A319702 Filter sequence for sequences that are constant for all even terms >= 2.
%C A319702 Restricted growth sequence transform of A141310.
%C A319702 For n > 2, a(n-1) is the number of occurrences of n in A319840. - _Stefano Spezia_, Apr 07 2023
%H A319702 Antti Karttunen, <a href="/A319702/b319702.txt">Table of n, a(n) for n = 1..100000</a>
%H A319702 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (0,2,0,-1).
%F A319702 a(1) = 1, and for n > 1, if n is even, a(n) = 2, otherwise a(n) = (n+3)/2.
%F A319702 From _Stefano Spezia_, Apr 07 2023: (Start)
%F A319702 O.g.f.: x*(1 + 2*x + x^2 - 2*x^3 - x^4)/((1 - x)^2*(1 + x)^2).
%F A319702 E.g.f.: ((4 + x)*cosh(x) + 3*sinh(x) - 2*(2 + x))/2. (End)
%o A319702 (PARI) A319702(n) = if(n<=2, n, if(!(n%2), 2, (n+3)/2));
%Y A319702 Cf. A141310, A319701, A319840.
%K A319702 nonn,easy
%O A319702 1,2
%A A319702 _Antti Karttunen_, Oct 02 2018