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A114840
Indices of Fibonacci numbers with 5 distinct prime factors.
3
30, 36, 42, 44, 45, 50, 57, 63, 66, 68, 69, 75, 76, 98, 111, 118, 124, 134, 141, 153, 169, 172, 183, 185, 201, 202, 203, 213, 218, 229, 247, 253, 267, 302, 303, 329, 335, 347, 363, 371, 373, 377, 381, 382, 386, 395, 398, 413, 415, 439, 443, 461
OFFSET
1,1
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..116 (terms 1..106 from Max Alekseyev)
FORMULA
{n: A022307(n)=5}. - R. J. Mathar, Nov 29 2015
EXAMPLE
a(1)=30 because 30th fibonacci number consists of 5 distinct prime factors (i.e., 832040 = 2^3 * 5 * 11 * 31 * 61).
PROG
(PARI) n=1; while(n<305, if(omega(fibonacci(n))==5, print1(n, ", ")); n++)
CROSSREFS
Column k=5 of A303217.
Sequence in context: A138689 A257447 A257440 * A284787 A214408 A350353
KEYWORD
nonn
AUTHOR
Shyam Sunder Gupta, Feb 19 2006
EXTENSIONS
More terms from Ryan Propper, Apr 26 2006
a(56)-a(106) from Max Alekseyev, Aug 18 2013
STATUS
approved