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A025513 Exactly half of first a(n) terms of A022300 are 1's (not known to be infinite). 2


%S 5904,5986,6050,6068,6074,6076,6078,6080,6084,6086,6092,6094,6096,

%T 6098,6100,6102,6104,6106,6108,6114,6116,6118,6120,6124,6126,6136,

%U 6138,6142,6144,6146,6148,6154,6156,6158,6160,6162,6164,6166,6168,6170,6174,6176

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

%C Even numbers n such that A025512(n/2) <= n and A025512(n/2+1) > n. - _Robert Israel_, Nov 02 2016

%H Robert Israel, <a href="/A025513/b025513.txt">Table of n, a(n) for n = 1..10000</a>

%p N:= 10000: # to use A022300(1..N)

%p B:= Vector(N):

%p B[1..4]:= <1,1,2,1>:

%p m:= 4: t:= 2:

%p for n from 1 while m < N do

%p t:= 3-t;

%p B[m]:= t;

%p if B[n] = 2 and m+1 < N then

%p B[m+1]:= t; m:= m+2

%p else m:= m+1

%p fi

%p od:

%p S:= ListTools:-PartialSums(convert(B,list)):

%p select(t -> S[t] = 3/2*t, [$1..nops(S)]); # _Robert Israel_, Nov 02 2016

%Y Cf. A022300, A025512.

%K nonn

%O 1,1

%A _David W. Wilson_

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Last modified November 30 09:34 EST 2021. Contains 349419 sequences. (Running on oeis4.)