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Fibonacci numbers whose digits, when squared, sum to a prime.
1

%I #11 Nov 21 2013 12:50:06

%S 21,377,610,2584,17711,75025,196418,514229,63245986,701408733,

%T 1134903170,1836311903,2971215073,17167680177565,72723460248141,

%U 117669030460994,2880067194370816120,19740274219868223167,354224848179261915075,1500520536206896083277

%N Fibonacci numbers whose digits, when squared, sum to a prime.

%H Vincenzo Librandi, <a href="/A181364/b181364.txt">Table of n, a(n) for n = 1..200</a>

%e a(5)=17711=Fib(22) since 1^2+7^2+7^2+1^2+1^2=1+49+49+1+1=101 is a prime

%t Select[Fibonacci[Range[150]],PrimeQ[Total[IntegerDigits[#]^2]]&] (* _Harvey P. Dale_, Feb 27 2012 *)

%Y Cf. A065398

%K nonn,base

%O 1,1

%A _Carmine Suriano_, Oct 15 2010

%E Corrected and extended by Harvey P. Dale, Feb 27 2012