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Numbers that are not the sum of two nonzero Fibonacci numbers.
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%I #12 Jun 18 2013 15:16:30

%S 1,12,17,19,20,25,27,28,30,31,32,33,38,40,41,43,44,45,46,48,49,50,51,

%T 52,53,54,59,61,62,64,65,66,67,69,70,71,72,73,74,75,77,78,79,80,81,82,

%U 83,84,85,86,87,88,93,95,96,98,99,100,101,103,104,105,106,107,108,109

%N Numbers that are not the sum of two nonzero Fibonacci numbers.

%C Except for the initial 1, each term can be expressed as the sum of a Fibonacci number and a non-Fibonacci number (A001690) and is thus the sum of three or more Fibonacci numbers. - _Alonso del Arte_, Jun 18 2013

%C That is, aside from the first term, numbers n such that A007895(n) > 2. - _Charles R Greathouse IV_, Jun 18 2013

%H Charles R Greathouse IV, <a href="/A059390/b059390.txt">Table of n, a(n) for n = 1..10000</a>

%t Complement[ Range[ Fibonacci[ 12 ]], Union[ Flatten[ Table[ Fibonacci[i] + Fibonacci[j], {i, 12}, {j, i - 1}]]]] (* _Robert G. Wilson v_, Jul 22 2005 *)

%o (PARI) is(n)=if(n<9,return(n==1)); my(k);while(fibonacci(k++)<=n,); n-=fibonacci(k-1); k=n^2; k+=(k+1)<<2; !issquare(k) && !issquare(k-8) \\ _Charles R Greathouse IV_, Jun 18 2013

%Y Complement of A059389.

%K nonn,easy

%O 1,2

%A Avi Peretz (njk(AT)netvision.net.il), Jan 29 2001

%E More terms from Larry Reeves (larryr(AT)acm.org), Jan 31 2001