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 A104162 Indicator sequence for the Fibonacci numbers. 17
 1, 2, 1, 1, 0, 1, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Without multiplicities, this is A010056. The number of nonnegative integer solutions of x^4 - 10*n^2*x^2 + 25*n^4 - 16 = 0. - Hieronymus Fischer, May 17 2007 LINKS FORMULA G.f.: sum{k>=0, x^F(k)} a(n) = 1+floor(arcsinh(sqrt(5)*n/2)/log(phi))-ceiling(arccosh(sqrt(5)*n/2)/log(phi)), for n>0, where phi=(1+sqrt(5))/2. Also true: a(n)=A108852(n)-A108852(n-1)=A130233(n)-A130233(n-1)=1+A130233(n)-A130234(n) for n>0 and a(n)=A130234(n+1)-A130234(n) for n>=0. - Hieronymus Fischer, May 17 2007 EXAMPLE a(1)=2 since F(1)=F(2)=1. PROG (PARI) a(n)=if(k==1, return(2)); my(k=n^2); k+=((k + 1) << 2); issquare(k) || issquare(k-8) \\ Charles R Greathouse IV, Feb 03 2014 CROSSREFS Cf. A000045. Partial sums are in A108852. See also A130233 and A130234. Sequence in context: A160381 A089311 A086784 * A145679 A007273 A016319 Adjacent sequences:  A104159 A104160 A104161 * A104163 A104164 A104165 KEYWORD easy,nonn AUTHOR Paul Barry, Apr 01 2005 STATUS approved

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Last modified December 18 18:43 EST 2018. Contains 318243 sequences. (Running on oeis4.)