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Positive numbers that are not the sum of two squares and a positive Fibonacci number.
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%I #4 Mar 11 2016 23:43:25

%S 256,384,872,1224,1512,1728,2661,2675,2824,3528,4656,5150,5224,6016,

%T 6024,6336,6592,6840,7193,7528,7560,7664,8016,8456,8512,8952,8968,

%U 9072,9696,9796,10032,10300,10440,10624,11000,11184,11208,11256,11640,11880

%N Positive numbers that are not the sum of two squares and a positive Fibonacci number.

%C There are 2142682 such numbers up to 10^9, the last one in this range being 999999456.

%o (PARI) isA001481(n)=#bnfisintnorm(bnfinit(z^2+1), n)

%o is(n)=my(k=1,f); while((f=fibonacci(k++))<=n, if(isA001481(n-f), return(0))); 1 \\ _Charles R Greathouse IV_, Mar 11 2016

%Y Cf. A115171, A115172, A115173, A115174, A115175, A115177.

%K nonn

%O 1,1

%A _Giovanni Resta_, Jan 15 2006