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%I #33 Oct 22 2023 16:57:38
%S 1,2,2,4,3,6,4,8,5,9,6,12,7,12,10,16,9,18,10,20,13,18,12,24,13,21,16,
%T 28,15,30,16,32,19,27,21,36,19,30,22,40,21,42,22,42,40,36,24,48,25,39,
%U 28,49,27,54,36,56,31,45,30,60,31,48,36,64,41,66,34,63,37,56,36,72,37,57,61,70,50,77,40,80
%N Height of the ziggurat of order n described in A347186.
%C The values of a(n) where a(n) = n give A174973.
%C The values of a(n) where a(n) is not equal to n give A238524.
%C If n is an odd prime then a(n) = (n + 1)/2.
%C Since this is a supersequence of A174973 so all powers of 2 and all even perfect numbers are in the sequence.
%C Shares infinitely many terms with A365195 from which first differs at a(15).
%F a(2*n-1) >= n.
%Y Row lengths of A365434.
%Y Cf. A000079, A000396, A065091, A174973, A196020, A235791, A236104, A237270, A237271, A237591, A237593, A238524, A245092, A262626, A347186, A347263, A347367, A365195.
%K nonn
%O 1,2
%A _Omar E. Pol_, Oct 18 2023