The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A160664 a(n) = a(n-1) + A000203(n), a(0)=1. 4
 1, 2, 5, 9, 16, 22, 34, 42, 57, 70, 88, 100, 128, 142, 166, 190, 221, 239, 278, 298, 340, 372, 408, 432, 492, 523, 565, 605, 661, 691, 763, 795, 858, 906, 960, 1008, 1099, 1137, 1197, 1253, 1343, 1385, 1481 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS Charles R Greathouse IV, Table of n, a(n) for n = 0..10000 FORMULA a(n) = 1 + A024916(n). - R. J. Mathar, May 25 2009 a(n) = 9 + A092406(n) for n>3. - Greg Dresden, Feb 23 2020 MAPLE ListTools:-PartialSums(map(numtheory:-sigma, [1, \$1..100])); # Robert Israel, Dec 19 2016 MATHEMATICA lst = {1}; a = 1; Do[a = a + DivisorSigma[1, n]; AppendTo[lst, a], {n, 80}]; lst (* Carl Najafi, Aug 21 2011 *) Transpose[NestList[{First[#]+1, Last[#]+DivisorSigma[1, First[#]+1]}&, {0, 1}, 50]][[2]] (* Harvey P. Dale, May 05 2012 *) PROG (PARI) a(n)=1+sum(k=1, n, sigma(k)) \\ Charles R Greathouse IV, Aug 22 2011 CROSSREFS Cf. A054519, A092406, A024916. - Greg Dresden, Feb 23 2020 Sequence in context: A045649 A267694 A024519 * A345140 A072829 A169740 Adjacent sequences:  A160661 A160662 A160663 * A160665 A160666 A160667 KEYWORD nonn AUTHOR Ctibor O. Zizka, May 22 2009 EXTENSIONS More terms from Carl Najafi, Aug 21 2011 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified August 14 05:20 EDT 2022. Contains 356110 sequences. (Running on oeis4.)