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A102299
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Number of prime divisors with multiplicity of n where n and n+1 are composite or twin composite numbers.
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0
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3, 2, 2, 2, 3, 2, 4, 2, 2, 3, 5, 2, 2, 2, 2, 2, 3, 3, 5, 2, 3, 2, 4, 2, 4, 2, 2, 3, 6, 2, 3, 2, 2, 3, 3, 2, 5, 4, 4, 2, 2, 2, 4, 2, 3, 2, 2, 2, 3, 3, 4, 3, 3, 2, 3, 2, 3, 3, 2, 2, 5, 2, 2, 2, 3, 3, 7, 2, 4, 2, 2, 4, 4, 2, 2, 2, 6, 2, 2, 3, 4, 3, 3, 2, 2, 2, 6, 2, 3, 3, 5, 2, 3, 3, 3, 3, 5, 2, 3, 2, 4, 2, 3, 2, 3
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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EXAMPLE
| For n=8 n+1=9 a twin composite pair. 8=2*2*2 or product of 3 prime divisors
with multiplicity.
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MATHEMATICA
| Total[Transpose[FactorInteger[#]][[2]]]&/@Transpose[Select[Partition[Complement[Range[250], Prime[Range[PrimePi[250]]]], 2, 1], #[[2]]-#[[1]]==1&]][[1]]
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PROG
| (PARI) f1(n) = for(x=1, n, y=composite(x); if(!isprime(y+1), print1(bigomega(y)", "))) composite(n) =\The n-th composite number. 1 is def as not prime nor composite. { local(c, x); c=1; x=1; while(c <= n, x++; if(!isprime(x), c++); ); return(x) }
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CROSSREFS
| Sequence in context: A127599 A085034 A119323 * A141070 A163751 A067279
Adjacent sequences: A102296 A102297 A102298 * A102300 A102301 A102302
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KEYWORD
| easy,nonn
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AUTHOR
| Cino Hilliard (hillcino368(AT)gmail.com), Feb 19 2005
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EXTENSIONS
| Mathematica program provided by Harvey P. Dale, Nov. 25, 2010
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