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A060319
Smallest Fibonacci number with n distinct prime factors.
14
1, 2, 21, 610, 6765, 832040, 102334155, 190392490709135, 1548008755920, 23416728348467685, 2880067194370816120, 81055900096023504197206408605, 2706074082469569338358691163510069157, 5358359254990966640871840, 57602132235424755886206198685365216, 18547707689471986212190138521399707760
OFFSET
0,2
EXAMPLE
a(5) = F(30) = 832040 = 2^3 * 5 * 11 * 41 * 61.
MATHEMATICA
f[n_]:=Length@FactorInteger[Fibonacci[n]]; lst={}; Do[Do[If[f[n]==q, Print[Fibonacci[n]]; AppendTo[lst, Fibonacci[n]]; Break[]], {n, 280}], {q, 18}]; lst (* Vladimir Joseph Stephan Orlovsky, Nov 23 2009 *)
First /@ SortBy[#, Last] &@ Map[#[[1]] &, Values@ GroupBy[#, Last]] &@ Table[{#, PrimeNu@ #} &@ Fibonacci@ n, {n, 2, 200}] (* Michael De Vlieger, Feb 18 2017, Version 10 *)
CROSSREFS
Row n=1 of A303218.
Sequence in context: A320653 A302686 A078602 * A095224 A034984 A024233
KEYWORD
nonn
AUTHOR
Labos Elemer, Mar 28 2001
STATUS
approved