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A114820
Indices of Fibonacci numbers with 11 prime factors when counted with multiplicity.
2
138, 140, 160, 190, 208, 222, 230, 250, 261, 285, 310, 318, 345, 351, 387, 388, 399, 402, 426, 469, 470, 483, 485, 488, 498, 507, 508, 518, 531, 534, 549, 568, 596, 598, 632, 656, 671, 678, 686, 688, 703, 715, 786, 788, 806, 808, 844, 872, 873, 874, 902
OFFSET
1,1
EXAMPLE
a(1)=138 because the 138th Fibonacci number (i.e., 30960598847965113057878492344) consists of 11 prime factors (i.e., 2*2*2*137*139*461*691*829*18077*28657*1485571).
MATHEMATICA
Select[Range[1000], PrimeOmega[Fibonacci[#]]==11&] (* Harvey P. Dale, Jan 09 2022 *)
PROG
(PARI) n=1; while(n<320, if(bigomega(fibonacci(n))==11, print1(n, ", ")); n++)
CROSSREFS
Column k=11 of A303215.
Sequence in context: A351237 A292094 A031964 * A107939 A008888 A045045
KEYWORD
hard,nonn
AUTHOR
Shyam Sunder Gupta, Feb 19 2006
EXTENSIONS
More terms from Ryan Propper, May 24 2006
STATUS
approved