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 A100382 Record values of A062700. 2
 3, 7, 13, 31, 127, 307, 1093, 1723, 2801, 3541, 8191, 10303, 19531, 28057, 30941, 131071, 147073, 524287, 797161, 830833, 1191373, 1204507, 1353733, 1395943, 1424443, 1482307, 1886503, 2037757, 2212657, 2432041, 2507473, 2922391 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Take sequence A062700: 3, 7, 13, 31, 31, 127, 307, 1093, 1723, 2801, 3541, 8191, 5113, 8011, 10303, .... Then eliminate terms so that each term of the sequence is larger than the preceding one: 3, 7, 13, 31, 127, 307, 1093, 1723, 2801, 3541, 8191, 10303, .... LINKS Chai Wah Wu, Table of n, a(n) for n = 1..10000 PROG (Magma) S:=[]; a:=0; for n in [1..3000000] do c:=SumOfDivisors(n); if IsPrime(c) and a lt c then Append(~S, c); a:=c; end if; end for; S; // Klaus Brockhaus, Oct 21 2009 CROSSREFS Cf. A062700 (terms of A000203 that are prime), A000203 (sigma(n), sum of divisors of n), A034885 (record values of sigma(n)). Sequence in context: A253850 A087578 A023195 * A292448 A222227 A152981 Adjacent sequences: A100379 A100380 A100381 * A100383 A100384 A100385 KEYWORD nonn AUTHOR Jorge Coveiro, Dec 30 2004 EXTENSIONS More terms from Ryan Propper, Jul 13 2005 Edited, corrected and extended by Klaus Brockhaus, Oct 21 2009 STATUS approved

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Last modified August 6 06:14 EDT 2024. Contains 374960 sequences. (Running on oeis4.)