

A062731


Sum of divisors of 2*n.


9



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
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OFFSET

1,1


LINKS

Harry J. Smith, Table of n, a(n) for n=1,...,1000


FORMULA

a(n) = A000203(2*n).  R. J. Mathar, Apr 06 2011


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))
(MuPad) numlib::sigma(2*n)$ n=0..81 // Zerinvary Lajos, May 13 2008
(PARI) { for (n=1, 1000, write("b062731.txt", n, " ", sigma(2*n)) ) } \\ Harry J. Smith, Aug 09 2009
(MAGMA) [SumOfDivisors(2*n): n in [1..70]]; // Vincenzo Librandi, Oct 31 2014


CROSSREFS

Cf. A008438, A074400.
Sequence in context: A081695 A142958 A187481 * A236375 A083031 A189927
Adjacent sequences: A062728 A062729 A062730 * A062732 A062733 A062734


KEYWORD

easy,nonn


AUTHOR

Jason Earls (zevi_35711(AT)yahoo.com), Jul 11 2001


EXTENSIONS

Zero removed and offset corrected by Omar E. Pol, Jul 17 2009


STATUS

approved



