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A164318
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Primes p such that the sum of divisors of p-1 is larger than 2*p.
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2
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13, 19, 31, 37, 41, 43, 61, 67, 71, 73, 79, 89, 97, 101, 103, 109, 113, 127, 139, 151, 157, 163, 181, 193, 197, 199, 211, 223, 229, 241, 271, 277, 281, 283, 307, 313, 331, 337, 349, 353, 367, 373, 379, 397, 401, 409, 421, 433, 439, 449, 457, 461, 463, 487, 491
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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EXAMPLE
| p=13 is in the sequence because A000203(12) = A008332(6) = 28 > 2*p.
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MATHEMATICA
| f[n_]:=Plus@@Divisors[n]; lst={}; Do[p=Prime[n]; If[f[p-1]>2*p, AppendTo[lst, p]], {n, 6!}]; lst
Select[Prime[Range[100]], DivisorSigma[1, #-1]>2#&] (* From Harvey P. Dale, Mar 31 2011 *)
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CROSSREFS
| Cf. A008332, A140557.
Sequence in context: A141562 A108097 A102764 * A092738 A115093 A158195
Adjacent sequences: A164315 A164316 A164317 * A164319 A164320 A164321
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KEYWORD
| nonn
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AUTHOR
| Vladimir Orlovsky (4vladimir(AT)gmail.com), Aug 12 2009
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EXTENSIONS
| Edited by R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Aug 21 2009
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