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A103665
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Primes p such that the number of divisors of p-1 is greater than the number of divisors of p+1.
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6
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13, 31, 37, 43, 61, 67, 73, 97, 101, 109, 113, 127, 151, 157, 163, 181, 193, 211, 229, 241, 257, 271, 277, 281, 283, 313, 331, 337, 353, 373, 379, 397, 401, 409, 421, 433, 457, 463, 487, 521, 523, 541, 547, 571, 577, 601, 613, 617, 631, 641, 661, 673, 677
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| Mathematica coding by Wouter Meeussen (wouter.meeussen(AT)pandora.be) and Robert G. Wilson v (rgwv(AT)rgwv.com).
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EXAMPLE
| a(1)=13 because d(12)=6 > d(14)=4.
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MATHEMATICA
| Select[Prime[Range[2, 140]], Length[Divisors[ # - 1]] > Length[Divisors[ # + 1]] &]
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CROSSREFS
| Cf. A008328 number of divisors of p-1, A008329 number of divisors of p+1, A103664, A103666, A103667.
Sequence in context: A046414 A023694 A038465 * A040050 A040086 A176181
Adjacent sequences: A103662 A103663 A103664 * A103666 A103667 A103668
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KEYWORD
| nonn
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AUTHOR
| Hugo Pfoertner (hugo(AT)pfoertner.org), Feb 19 2005
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