A114816 Indices of Fibonacci numbers with 7 prime factors when counted with multiplicity.

30, 42, 56, 66, 70, 81, 104, 105, 136, 148, 152, 164, 175, 195, 207, 212, 244, 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

Offset

1,1

Links

Amiram Eldar, Table of n, a(n) for n = 1..112

Blair Kelly, Fibonacci and Lucas Factorizations.

Example

a(1) = 30 because 30th Fibonacci number (i.e., 832040) consists of 7 prime factors (i.e., 2*2*2*5*11*31*61).

Mathematica

t = {}; Do[f = FactorInteger[Fibonacci[n]]; If[Total[Transpose[f][[2]]] == 7, AppendTo[t, n]], {n, 2, 100}]; t (* T. D. Noe, Mar 14 2014 *)

Prog

(PARI) n=1; while(n<310, if(bigomega(fibonacci(n))==7, print1(n, ", ")); n++)

Crossrefs

Cf. A000045.

Column k=7 of A303215.

Sequence in context: A097036 A090790 A090800 * A299991 A000977 A214195

Adjacent sequences: A114813 A114814 A114815 * A114817 A114818 A114819

Keyword

nonn

Author

Shyam Sunder Gupta, Feb 19 2006

Extensions

More terms from Ryan Propper, May 22 2006

Status

approved