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A241289
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Numbers n for which in the factorization of n! over distinct terms of A050376, the numbers of prime and nonprime terms are equal.
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2
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OFFSET
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1,1
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COMMENTS
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a(10), if it exists, should be more than 5000. Is a(9)=71 the last term of sequence? - Peter J. C. Moses, Apr 19 2014
One can prove that a(9)=71 indeed is the last term of this sequence. - Vladimir Shevelev, Apr 19 2014.
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REFERENCES
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V. S. Shevelev, Multiplicative functions in the Fermi-Dirac arithmetic, Izvestia Vuzov of the North-Caucasus region, Nature sciences 4 (1996), 28-43 [Russian].
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LINKS
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Table of n, a(n) for n=1..9.
S. Litsyn and V. S. Shevelev, On factorization of integers with restrictions on the exponent, INTEGERS: Electronic Journal of Combinatorial Number Theory, 7 (2007), #A33, 1-36.
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EXAMPLE
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7 is in the sequence, since 7! in the considered factorization is 5*7*9*16, and here we have 2 primes and 2 nonprimes.
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CROSSREFS
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Cf. A177329, A177333, A177334, A240537, A240606, A240619, A240620, A240668, A240669, A240670, A240672, A240695, A240751, A240755, A240764, A240905, A240906, A241123, A241124, A241139, A241148.
Sequence in context: A297131 A289740 A289760 * A037369 A076599 A067197
Adjacent sequences: A241286 A241287 A241288 * A241290 A241291 A241292
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KEYWORD
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nonn,fini,full
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AUTHOR
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Vladimir Shevelev, Apr 18 2014
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EXTENSIONS
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Terms a(7) - a(9) from Peter J. C. Moses, Apr 19 2014
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STATUS
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approved
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