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A025513 Exactly half of first a(n) terms of A022300 are 1's (not known to be infinite).

%I A025513 #12 Nov 03 2016 01:38:21
%S A025513 5904,5986,6050,6068,6074,6076,6078,6080,6084,6086,6092,6094,6096,
%T A025513 6098,6100,6102,6104,6106,6108,6114,6116,6118,6120,6124,6126,6136,
%U A025513 6138,6142,6144,6146,6148,6154,6156,6158,6160,6162,6164,6166,6168,6170,6174,6176
%N A025513 Exactly half of first a(n) terms of A022300 are 1's (not known to be infinite).
%C A025513 Even numbers n such that A025512(n/2) <= n and A025512(n/2+1) > n. - _Robert Israel_, Nov 02 2016
%H A025513 Robert Israel, <a href="/A025513/b025513.txt">Table of n, a(n) for n = 1..10000</a>
%p A025513 N:= 10000: # to use A022300(1..N)
%p A025513 B:= Vector(N):
%p A025513 B[1..4]:= <1,1,2,1>:
%p A025513 m:= 4: t:= 2:
%p A025513 for n from 1 while m < N do
%p A025513   t:= 3-t;
%p A025513   B[m]:= t;
%p A025513   if B[n] = 2 and m+1 < N then
%p A025513      B[m+1]:= t; m:= m+2
%p A025513   else m:= m+1
%p A025513   fi
%p A025513 od:
%p A025513 S:= ListTools:-PartialSums(convert(B,list)):
%p A025513 select(t -> S[t] = 3/2*t, [$1..nops(S)]); # _Robert Israel_, Nov 02 2016
%Y A025513 Cf. A022300, A025512.
%K A025513 nonn
%O A025513 1,1
%A A025513 _David W. Wilson_