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Search: id:A023023
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%I A023023
%S A023023 1,1,2,2,4,4,6,6,10,8,14,12,16,16,24,18,30,24,32,30,44,32,50,42,54,48,
               70,
%T A023023 48,80,64,80,72,96,72,114,90,112,96,140,96,154,120,144,132,184,128,196,
%U A023023 150,192,168,234,162,240,192,240,210,290,192,310,240,288,256,336,240,374
%N A023023 Number of partitions of n into 3 unordered relatively prime parts.
%H A023023 Mohamed El Bachraoui, <a href="http://math.univ-lille1.fr/~ramare/AAA/
               Abstracts/ElBachraoui.pdf">Partitions with relatively prime parts</
               a> [From Jonathan Sondow (jsondow(AT)alumni.princeton.edu), May 27 
               2009]
%F A023023 G.f. for the number of partitions of n into m unordered relatively prime 
               parts is Sum(moebius(k)*x^(m*k)/Product(1-x^(i*k), i=1..m), k=1..infinity). 
               - Vladeta Jovovic (vladeta(AT)eunet.rs), Dec 21 2004
%F A023023 a(n) = (n^2/12)*Product_{prime p|n} (1 - 1/p^2) for n > 3 (proved by 
               Mohamed El Bachraoui). [From Jonathan Sondow (jsondow(AT)alumni.princeton.edu), 
               May 27 2009]
%Y A023023 Cf. A023022-A023030, A000741-A000743, A023031-A023035, A101271.
%Y A023023 Sequence in context: A001362 A001310 A029009 this_sequence A008643 A008644 
               A008645
%Y A023023 Adjacent sequences: A023020 A023021 A023022 this_sequence A023024 A023025 
               A023026
%K A023023 nonn
%O A023023 3,3
%A A023023 David W. Wilson (davidwwilson(AT)comcast.net)

    
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Last modified November 30 13:13 EST 2009. Contains 167758 sequences.


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