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Search: id:A053409
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A053409 Fibonacci numbers which are semiprimes. +0
8
21, 34, 55, 377, 4181, 17711, 121393, 1346269, 5702887, 165580141, 53316291173, 956722026041, 2504730781961, 308061521170129, 806515533049393, 14472334024676221, 1779979416004714189, 19740274219868223167 (list; graph; listen)
OFFSET

1,1

EXAMPLE

a(1)=21 because 21 is the product of two primes.

CROSSREFS

Cf. A000045, A000040, A001358.

Cf. A072381.

Sequence in context: A135595 A082483 A075735 this_sequence A144205 A008946 A095738

Adjacent sequences: A053406 A053407 A053408 this_sequence A053410 A053411 A053412

KEYWORD

nonn

AUTHOR

G. L. Honaker, Jr. (honak3r(AT)gmail.com), Jan 09 2000

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Last modified December 15 00:47 EST 2009. Contains 170825 sequences.


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