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A141241
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a(n) = number of divisors of n-th positive integer with a nonprime number of divisors. a(n) = the number of divisors of A139118(n).
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1
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1, 4, 4, 4, 6, 4, 4, 6, 6, 4, 4, 8, 4, 4, 6, 8, 6, 4, 4, 4, 9, 4, 4, 8, 8, 6, 6, 4, 10, 6, 4, 6, 8, 4, 8, 4, 4, 12, 4, 6, 4, 8, 6, 4, 8, 12, 4, 6, 6, 4, 8, 10, 4, 12, 4, 4, 4, 8, 12, 4, 6, 4, 4, 4, 12, 6, 6, 9, 8, 8, 8, 4, 12, 8, 4, 10, 8, 4, 6, 6, 4, 4, 16, 4, 4, 6, 4, 12, 8, 4, 8, 12, 4, 4, 8, 8, 8, 12, 4
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| a(1) = 1 and all other terms are composite, of course.
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PROG
| (PARI) for(i=1, 200, if(!isprime(numdiv(i)), print1(numdiv(i)", "))) [From Franklin T. Adams-Watters (FrankTAW(AT)Netscape.net), Apr 09 2009]
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CROSSREFS
| Cf. A139118, A141242.
Sequence in context: A010304 A164821 A130331 * A140696 A160401 A114742
Adjacent sequences: A141238 A141239 A141240 * A141242 A141243 A141244
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KEYWORD
| nonn
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AUTHOR
| Leroy Quet Jun 16 2008
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EXTENSIONS
| More terms from Franklin T. Adams-Watters (FrankTAW(AT)Netscape.net), Apr 09 2009
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