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A100382 Record values of A062700. 1
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; 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, ....

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; [From 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: A069246 A087578 A023195 * A152981 A112040 A084611

Adjacent sequences:  A100379 A100380 A100381 * A100383 A100384 A100385

KEYWORD

nonn

AUTHOR

Jorge Coveiro (jorgecoveiro(AT)yahoo.com), Dec 30 2004

EXTENSIONS

More terms from Ryan Propper (rpropper(AT)stanford.edu), Jul 13 2005

Edited, corrected and extended by Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Oct 21 2009

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Last modified February 17 00:09 EST 2012. Contains 205978 sequences.