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A250743
Numerator of the harmonic mean of the first n positive Fibonacci numbers.
2
1, 1, 6, 24, 150, 720, 1560, 87360, 1670760, 20420400, 1999157160, 13085392320, 3302971111440, 103154328557280, 1348374437570160, 67598505136850688, 114701988497522458032, 2307534121538392979232, 10183789060049355548733936
OFFSET
1,3
LINKS
EXAMPLE
a(4) = 24 because the first 4 positive Fibonacci numbers are [1,1,2,3], and 4/(1/1+1/1+1/2+1/3) = 24/17.
PROG
(PARI) s=vector(30); f=Vec(x/(1-x-x^2)+O(x^(#s+1))); n=d=0; for(k=1, #s, n++; d+=1/f[k]; s[k]=numerator(n/d)); s
CROSSREFS
Cf. A000045 (Fibonacci numbers), A250744 (denominators).
Sequence in context: A126267 A026947 A366757 * A265883 A330498 A165491
KEYWORD
nonn,frac
AUTHOR
Colin Barker, Nov 27 2014
STATUS
approved