A114822 - OEIS

%I #15 May 05 2024 19:19:33

%S 84,132,156,162,224,234,260,354,364,368,405,434,438,455,472,512,536,

%T 584,585,595,610,615,645,693,741,775,777,822,830,834,867,904,931,957,

%U 962,1001,1025,1045,1066,1070,1102,1106,1108,1146,1147,1158,1209,1268,1309,1310,1317,1334,1335,1388

%N Indices of Fibonacci numbers with 13 prime factors when counted with multiplicity.

%H Blair Kelly, <a href="http://mersennus.net/fibonacci/">Fibonacci and Lucas Factorizations</a>.

%e a(1)=84 because the 84th Fibonacci number (i.e., 160500643816367088) consists of 13 prime factors (i.e., 2*2*2*2*3*3*13*29*83*211*281*421*1427).

%o (PARI) n=1;while(n<360,if(bigomega(fibonacci(n))==13,print1(n,", "));n++)

%Y Column k=13 of A303215.

%K hard,nonn

%O 1,1

%A _Shyam Sunder Gupta_, Feb 19 2006

%E More terms from _Ryan Propper_, May 24 2006

%E More terms from _Amiram Eldar_, Oct 14 2019