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A065106
Smallest Fibonacci index to produce a factor p^2 (for primes p).
3
6, 12, 25, 56, 91, 110, 153, 342, 406, 552, 703, 752, 820, 915, 930, 979
OFFSET
1,1
COMMENTS
Following Lucas, these might be called the prime-squared ranks of apparition.
Assuming that there are no square primitive factors in the Fibonacci sequence (an open question), then this sequence continues 1431, 1892, 2147, 2701, 2943, 3029, 3422, 3852, 4378, 4556, 4753, 4970, 5050, 5513, 6162, 6394, 6972, 7550, 7868, 8841, 8862, 9453. This is obtained by sorting the sequence prime(n)*A001602(n). - T. D. Noe, Apr 15 2004
EXAMPLE
342 is here but not in A065069 because Fib(342) is the first Fib divisible by 19^2, but 342 is divisible by 6 and so is not a primitive index.
CROSSREFS
Cf. A001602 (smallest m such that prime(n) divides Fibonacci(m)).
Sequence in context: A303398 A244743 A202805 * A264008 A283221 A177282
KEYWORD
nonn
AUTHOR
Len Smiley, Nov 21 2001
STATUS
approved