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 A062731 Sum of divisors of 2*n. 21
 3, 7, 12, 15, 18, 28, 24, 31, 39, 42, 36, 60, 42, 56, 72, 63, 54, 91, 60, 90, 96, 84, 72, 124, 93, 98, 120, 120, 90, 168, 96, 127, 144, 126, 144, 195, 114, 140, 168, 186, 126, 224, 132, 180, 234, 168, 144, 252, 171, 217, 216, 210, 162, 280, 216, 248, 240, 210 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(n) is also the total number of parts in all partitions of 2*n into equal parts. - Omar E. Pol, Feb 14 2021 LINKS N. J. A. Sloane, Table of n, a(n) for n = 1..20000 [First 1000 terms from Harry J. Smith] FORMULA a(n) = A000203(2*n). - R. J. Mathar, Apr 06 2011 a(n) = A000203(n) + A054785(n). - R. J. Mathar, May 19 2020 MATHEMATICA lst={}; Do[AppendTo[lst, DivisorSigma[1, n]], {n, 2, 6!, 2}]; lst (* Vladimir Joseph Stephan Orlovsky, Sep 20 2008 *) PROG (PARI) vector(66, n, sigma(2*n, 1)) (PARI) for (n=1, 1000, write("b062731.txt", n, " ", sigma(2*n)) ) \\ Harry J. Smith, Aug 09 2009 (MuPAD) numlib::sigma(2*n)\$ n=0..81 // Zerinvary Lajos, May 13 2008 (MAGMA) [SumOfDivisors(2*n): n in [1..70]]; // Vincenzo Librandi, Oct 31 2014 CROSSREFS Cf. A000203, A008438, A074400. Sequence in context: A310224 A310225 A310226 * A236375 A310227 A310228 Adjacent sequences:  A062728 A062729 A062730 * A062732 A062733 A062734 KEYWORD easy,nonn AUTHOR Jason Earls, Jul 11 2001 EXTENSIONS Zero removed and offset corrected by Omar E. Pol, Jul 17 2009 STATUS approved

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Last modified April 19 02:19 EDT 2021. Contains 343105 sequences. (Running on oeis4.)