A114821 Indices of Fibonacci numbers with 12 prime factors when counted with multiplicity.
48, 60, 90, 126, 176, 258, 297, 315, 375, 385, 410, 430, 441, 459, 474, 475, 496, 555, 609, 621, 627, 638, 682, 710, 711, 729, 734, 759, 805, 814, 826, 854, 875, 897, 903, 906, 908, 925, 932, 935, 981, 987, 994, 1022, 1067, 1089, 1105, 1244, 1246, 1251, 1265, 1285, 1341, 1348
Offset: 1
Examples
a(1)=48 because the 48th Fibonacci number (i.e., 4807526976) consists of 12 prime factors (i.e., 2*2*2*2*2*2*3*3*7*23*47*1103).
Links
- Blair Kelly, Fibonacci and Lucas Factorizations.
Crossrefs
Column k=12 of A303215.
Programs
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PARI
n=1;while(n<320,if(bigomega(fibonacci(n))==12,print1(n,", "));n++)
Extensions
More terms from Ryan Propper, May 24 2006
More terms from Amiram Eldar, Oct 14 2019