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A077646
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Solutions to LCM[x,tau[x]]=2x which are neither primes(p), nor even-primes [2p].
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0
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45, 63, 75, 90, 99, 117, 120, 126, 147, 150, 153, 168, 171, 198, 207, 216, 234, 243, 261, 264, 279, 280, 294, 306, 312, 333, 342, 363, 369, 387, 405, 408, 414, 420, 423, 440, 456, 477, 486, 507, 520, 522, 531, 540, 549, 552, 558, 603, 616, 639, 657, 660
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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FORMULA
| Composite solutions to A009530[x]=2x which are not twice a prime.
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EXAMPLE
| x=63, d[x]=tau[x]=3.2=6, LCM[63,6]=126=2x; If it was x=p(odd) or y=2p, then LCM[x,d[x]]=LCM[p,2]=2p or LCN[2p,4]=2p.
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CROSSREFS
| Cf. A009530, A001747, A000040, A065091.
Sequence in context: A138046 A140276 A140277 * A175761 A046364 A051773
Adjacent sequences: A077643 A077644 A077645 * A077647 A077648 A077649
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KEYWORD
| nonn
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AUTHOR
| Labos E. (labos(AT)ana.sote.hu), Nov 18 2002
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