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A117551
Indices of Fibonacci numbers with 15 distinct prime factors.
2
180, 210, 276, 280, 288, 312, 320, 340, 342, 416, 464, 476, 486, 516, 558, 564, 651, 665, 676, 708, 730, 735, 752, 776, 783, 837, 848, 856, 890, 992, 999, 1030, 1034, 1038, 1065, 1068, 1071, 1095, 1125, 1130, 1192, 1212
OFFSET
1,1
EXAMPLE
F(180) = 2^4 * 3^3 * 5 * 11 * 17 * 19 * 31 * 41 * 61 * 107 * 181 * 541 * 2521 * 109441 * 10783342081 has 15 distinct prime factors, so 180 is in the sequence.
PROG
(PARI) isok(n) = (omega(fibonacci(n)) == 15) \\ Michel Marcus, Jun 28 2013
CROSSREFS
Column k=15 of A303217.
Sequence in context: A154360 A253393 A260265 * A068545 A068403 A291457
KEYWORD
hard,more,nonn
AUTHOR
Ryan Propper, Apr 26 2006
EXTENSIONS
a(32)-a(42) from Max Alekseyev, Aug 18 2013
STATUS
approved