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 A056823 Counts members of A056808 by number of factors. 1
 0, 0, 0, 1, 3, 9, 21, 49, 106, 226, 470, 968, 1971, 3995, 8057, 16208, 32537, 65239, 130687, 261654, 523661, 1047784, 2096150, 4193049, 8387033, 16775258, 33551996, 67105854, 134214010, 268430891, 536865308, 1073734982, 2147475299 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,5 COMMENTS A056808 relates to least prime signatures (cf. A025487) a(n) is the number of redundant partitions of n. [From Omar E. Pol, Jan 31 2009] LINKS FORMULA A011782(n) - A000041(n) EXAMPLE A011782 begins 1 1 2 4 8 16 32 64 128 256 ...; A000041 begins 1 1 2 3 5 7 11 15 22 30 ...; hence a(n) = 0 0 0 1 3 9 21 49 106 226 ... For n = 3 the factorizations are 8=2*2*2, 12=2*2*3, 18=2*3*3 and 30 =2*3*5. MAPLE seq(count(Composition(n))-count(Partition(n)), n=1..32); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Oct 16 2006 CROSSREFS Cf. A000041, A011782, A025487 and A056808. Sequence in context: A000714 A090984 A006813 * A105544 A119917 A111209 Adjacent sequences:  A056820 A056821 A056822 * A056824 A056825 A056826 KEYWORD easy,nonn AUTHOR Alford Arnold, Aug 29 2000 EXTENSIONS More terms from James A. Sellers, Aug 31 2000 STATUS approved

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