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%I #36 Sep 08 2022 08:45:50
%S 10,14,65,391,1003,2602,10967,2178341,701408777,86267571326,
%T 591286729937,4052739537943,72723460248209,117669030461063,
%U 3416454622906783,61305790721611673,420196140727489759,2427893228399975082557,251728825683549488150424389
%N Semiprimes of the form Fibonacci(k) + k.
%C This is to A069108 as semiprimes are to primes. A002062(k) is semiprime for k = 5, 6, 10, 14, 16, 18, 21, 32, ...
%H Vincenzo Librandi, <a href="/A173684/b173684.txt">Table of n, a(n) for n = 1..24</a>
%F A002062 INTERSECTION A001358.
%e F(21) + 21 = 10967 = 11 * 997, thus 10967 is in the sequence.
%t Select[Table[Fibonacci[n]+n,{n,200}],PrimeOmega[#]==2&] (* _Harvey P. Dale_, Nov 02 2011 *)
%o (Magma) IsSemiprime:=func< n | &+[ k[2]: k in Factorization(n) ] eq 2 >; [ a: n in [1..100] | IsSemiprime(a) where a is n+Fibonacci(n) ]; // _Klaus Brockhaus_, Jan 27 2011
%Y Cf. A000045, A001358, A002062, A053409, A069108.
%K nonn
%O 1,1
%A _Jonathan Vos Post_, Jan 26 2011