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A059390
Numbers that are not the sum of two nonzero Fibonacci numbers.
3
1, 12, 17, 19, 20, 25, 27, 28, 30, 31, 32, 33, 38, 40, 41, 43, 44, 45, 46, 48, 49, 50, 51, 52, 53, 54, 59, 61, 62, 64, 65, 66, 67, 69, 70, 71, 72, 73, 74, 75, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 93, 95, 96, 98, 99, 100, 101, 103, 104, 105, 106, 107, 108, 109
OFFSET
1,2
COMMENTS
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
That is, aside from the first term, numbers n such that A007895(n) > 2. - Charles R Greathouse IV, Jun 18 2013
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
MATHEMATICA
Complement[ Range[ Fibonacci[ 12 ]], Union[ Flatten[ Table[ Fibonacci[i] + Fibonacci[j], {i, 12}, {j, i - 1}]]]] (* Robert G. Wilson v, Jul 22 2005 *)
PROG
(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
CROSSREFS
Complement of A059389.
Sequence in context: A278034 A087657 A248478 * A179243 A350686 A064825
KEYWORD
nonn,easy
AUTHOR
Avi Peretz (njk(AT)netvision.net.il), Jan 29 2001
EXTENSIONS
More terms from Larry Reeves (larryr(AT)acm.org), Jan 31 2001
STATUS
approved