A162462 Sum of all numbers from n to sigma(n).

1, 5, 7, 22, 11, 63, 15, 92, 55, 126, 23, 340, 27, 209, 195, 376, 35, 627, 39, 713, 318, 435, 47, 1554, 196, 578, 469, 1218, 59, 2193, 63, 1520, 648, 924, 581, 3556, 75, 1127, 855, 3315, 83, 3795, 87, 2624, 2091, 1593, 95, 6622, 477, 3146, 1353, 3525, 107, 5829, 1143

Offset

1,2

Links

Table of n, a(n) for n=1..55.

Formula

a(n) = n + (n+1) + ... + A000203(n) = A000217(A000203(n)) - A000217(n-1).

a(n) = Sum_{k=n..sigma(n)} k. - Wesley Ivan Hurt, Apr 20 2023

Example

a(1)=1=1. a(2)=5=2+3. a(3)=7=3+4. a(4)=22=4+5+6+7. a(5)=11=5+6. a(6)=63=6+7+8+9+10+11+12.

Mathematica

Total[Range[#, DivisorSigma[1, #]]]&/@Range[60] (* Harvey P. Dale, Feb 23 2023 *)

Crossrefs

Cf. A000203.

Sequence in context: A179189 A030735 A303189 * A165144 A084164 A036498

Adjacent sequences: A162459 A162460 A162461 * A162463 A162464 A162465

Keyword

nonn,easy

Author

Juri-Stepan Gerasimov, Jul 04 2009

Extensions

a(12), a(33), a(34) and others corrected by R. J. Mathar, Jul 06 2009

Status

approved