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%I #20 Aug 15 2019 21:35:29
%S 25,91,126,175,225,276,325,426,456,475,576,625,637,703,726,775,820,
%T 876,925,979,1001,1002,1026,1075,1176,1183,1225,1275,1326,1375,1431,
%U 1476,1525,1548,1625,1626,1675,1729,1776,1825,1926,1975,2076,2094,2125,2148,2226
%N Numbers n such that F(n) and F(n-1) are not squarefree where F(n) = A000045(n).
%C Utilized the factorization of Fibonacci numbers in the FactorDB.com database. - _Robert Price_, Feb 27 2017
%H Robert Price, <a href="/A280297/b280297.txt">Table of n, a(n) for n = 1..108</a>
%H FactorDB, <a href="http://factordb.com/index.php?query=In&use=n&n=1000&VP=on&VC=on&EV=on&OD=on&PR=on&FF=on&PRP=on&CF=on&U=on&C=on&perpage=20&format=1&sent=Show">Factorizations of F(1000) ... F(1019)</a>.
%e 25 is a term because Fibonacci(25) = 5^2 * 3001 and Fibonacci(24) = 2^5 * 3^2 * 7 * 23.
%o (PARI) is(n) = !issquarefree(fibonacci(n)) && !issquarefree(fibonacci(n-1));
%Y Cf. A000045, A013929, A037917.
%K nonn,more
%O 1,1
%A _Altug Alkan_, Dec 31 2016
%E a(8)-a(108) from _Robert Price_, Feb 27 2017
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