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A072396
Index of smallest Fibonacci number with n prime factors when counted with multiplicity.
5
3, 8, 6, 20, 18, 12, 30, 54, 24, 36, 138, 48, 84, 72, 108, 96, 210, 120, 276, 168, 216, 252, 288, 240, 336, 570, 384, 420, 360, 576, 480, 540, 504, 660, 600, 672, 990, 720, 792, 840, 1152, 1140
OFFSET
1,1
COMMENTS
1452 < a(43) <= 1596, a(44) = 1296, a(45) = 1368, a(46) = 1080, a(47) = 1200, a(48) <= 1728. - Daniel Suteu, Jan 19 2023
EXAMPLE
a(3) = 6 since the 6th Fibonacci number 8 has 3 prime factors.
PROG
(PARI) a(n) = my(k=1); while (bigomega(fibonacci(k)) != n, k++); k; \\ Michel Marcus, Aug 26 2020
CROSSREFS
Row n=1 of A303215.
Sequence in context: A225267 A320541 A366612 * A001175 A093725 A347118
KEYWORD
nonn,more
AUTHOR
Shyam Sunder Gupta, Jul 21 2002
EXTENSIONS
a(17)-a(24) from Alois P. Heinz, Apr 10 2018
a(25)-a(42) from Amiram Eldar, Aug 26 2020
STATUS
approved