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A114838
Indices of Fibonacci numbers with 7 distinct prime factors.
3
70, 81, 104, 105, 136, 148, 152, 164, 182, 186, 195, 207, 212, 244, 246, 254, 259, 289, 291, 292, 298, 305, 319, 326, 332, 344, 365, 367, 403, 404, 423, 445, 447, 451, 458, 478, 489, 511, 517, 519, 526, 533, 537, 543, 554, 565, 566, 597, 605, 679, 681, 685, 698, 699, 701, 721, 723, 725, 737, 745, 746, 749, 753, 758, 766, 767, 785, 813, 817, 831, 842, 871, 879, 901, 905, 914, 955, 967, 973, 985, 998, 1006, 1007, 1009, 1043, 1046, 1051, 1133, 1139, 1159, 1167, 1174, 1175, 1177, 1191, 1199, 1207, 1219
OFFSET
1,1
EXAMPLE
a(1)=70 because the 70th Fibonacci number consists of 7 distinct prime factors (i.e., 190392490709135 = 5 x 11 x 13 x 29 x 71 x 911 x 141961).
MATHEMATICA
Select[Range[1220], PrimeNu[Fibonacci[#]]==7&] (* Harvey P. Dale, Sep 18 2020 *)
PROG
(PARI) n=1; while(n<310, if(omega(fibonacci(n))==7, print1(n, ", ")); n++)
CROSSREFS
Column k=7 of A303217.
Sequence in context: A118216 A256082 A345487 * A036191 A165632 A295807
KEYWORD
nonn
AUTHOR
Shyam Sunder Gupta, Feb 19 2006
EXTENSIONS
More terms from Ryan Propper, Apr 26 2006
a(53)-a(98) from Max Alekseyev, Aug 18 2013
STATUS
approved