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A114843 Indices of Fibonacci numbers with 4 distinct prime factors. 2
20, 24, 27, 28, 32, 52, 55, 74, 77, 85, 87, 91, 93, 97, 115, 123, 143, 146, 149, 157, 161, 163, 178, 187, 197, 209, 211, 214, 215, 221, 223, 239, 242, 249, 262, 269, 283, 287, 307, 311, 313, 321, 334, 349, 379, 391, 393, 409, 421, 453, 487, 493, 499, 523, 581, 586, 617, 641, 647, 677, 691, 707, 709, 787, 794, 811, 823, 839, 853, 859, 887, 907, 913, 929, 941, 953, 1031, 1049, 1063, 1093, 1229 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..88

Blair Kelly, Fibonacci and Lucas Factorizations.

EXAMPLE

a(1)=20 because 20th fibonacci number consists of 4 distinct prime factors (i.e. 6765 = 3 x 5 x 11 x 41)

PROG

(PARI) n=1; while(n<350, if(omega(fibonacci(n))==4, print1(n, ", ")); n++)

CROSSREFS

Cf. A114823-A114826, A114836-A114841.

Column k=4 of A303217.

Sequence in context: A062908 A111323 A250289 * A174629 A221651 A108373

Adjacent sequences:  A114840 A114841 A114842 * A114844 A114845 A114846

KEYWORD

nonn

AUTHOR

Shyam Sunder Gupta, Feb 19 2006

EXTENSIONS

More terms from Ryan Propper, Apr 26 2006

a(56)-a(81) from Max Alekseyev, Aug 18 2013

STATUS

approved

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Last modified September 22 06:53 EDT 2020. Contains 337289 sequences. (Running on oeis4.)