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%I #16 Jun 18 2018 03:42:02
%S 0,1,13,144,806515533049393,61305790721611591,83621143489848422977,
%T 6356306993006846248183,155576970220531065681649693,
%U 78569350599398894027251472817058687522
%N Fibonacci numbers whose digits sum to a square.
%H Harry J. Smith, <a href="/A065411/b065411.txt">Table of n, a(n) for n = 1..50</a>
%e 144 is in the sequence because (1) it is a Fibonacci number and (2) the sum of its digits 1 + 4 + 4 = 9 is a square.
%o (PARI) {m=200;print1(0,",");for(n=2,m,a=fibonacci(n);s=0;k=a;while(k>0,d=divrem(k,10);k=d[1];s=s+d[2]);if(issquare(s),print1(a,",")))} \\ Luc Stevens (lms022(AT)yahoo.com), Apr 15 2006
%o (PARI) SumD(x)= { local(s=0); while (x>9, s+=x-10*(x\10); x\=10); return(s + x) } { n=0; for (m=0, 10^9, if (m==2, next); f=fibonacci(m); if (issquare(SumD(f)), write("b065411.txt", n++, " ", f); if (n==50, return)) ) } \\ _Harry J. Smith_, Oct 18 2009
%Y Cf. A000045.
%K base,nonn
%O 1,3
%A _Jason Earls_, Nov 22 2001
%E Entry revised by _N. J. A. Sloane_, Jul 23 2006
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