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1,3
Is this sequence finite?
See the graph of sequence A072931 for compelling evidence that 33 is the last term of this sequence. - T. D. Noe, Apr 11 2007
Table of n, a(n) for n=1..13.
a(10) = 11 since there is no way to represent 11 as a sum of two semiprimes. 13 is not a term since 13 = 4 + 9.
Cf. A001358.
Sequence in context: A214321 A005577 A263362 * A245761 A059759 A042952
Adjacent sequences: A072963 A072964 A072965 * A072967 A072968 A072969
nonn,more
Lior Manor Aug 13 2002
approved