A114843 Indices of Fibonacci numbers with 4 distinct prime factors.

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

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