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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A139586 Non-Fibonacci numbers with Fibonacci number of divisors.

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%I A139586 #11 May 12 2024 10:08:56
%S A139586 4,7,9,11,16,17,19,23,24,25,29,30,31,37,40,41,42,43,47,49,53,54,56,59,
%T A139586 61,66,67,70,71,73,78,79,81,83,88,97,101,102,103,104,105,107,109,110,
%U A139586 113,114,121,127,128,130,131,135,136,137,138
%N A139586 Non-Fibonacci numbers with Fibonacci number of divisors.
%C A139586 A000005(a(n)) is a Fibonacci number.
%e A139586 16 is a term because it is not a Fibonacci number and its number of divisors is 5, a Fibonacci number.
%t A139586 fibs=Fibonacci[Range[15]]; nonfibs=Complement[Range[fibs[[-1]]],fibs]; Select[nonfibs,MemberQ[fibs,DivisorSigma[0,#]]&] (* _Harvey P. Dale_, Jan 11 2011 *)
%Y A139586 Non-Fibonacci numbers: A001690.
%Y A139586 Cf. A000005, A000045, A139095, A139587, A139588, A139589, A139590.
%K A139586 easy,nonn
%O A139586 1,1
%A A139586 _Omar E. Pol_, May 22 2008