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%I #9 Apr 20 2023 17:59:14
%S 1,5,7,22,11,63,15,92,55,126,23,340,27,209,195,376,35,627,39,713,318,
%T 435,47,1554,196,578,469,1218,59,2193,63,1520,648,924,581,3556,75,
%U 1127,855,3315,83,3795,87,2624,2091,1593,95,6622,477,3146,1353,3525,107,5829,1143
%N Sum of all numbers from n to sigma(n).
%F a(n) = n + (n+1) + ... + A000203(n) = A000217(A000203(n)) - A000217(n-1).
%F a(n) = Sum_{k=n..sigma(n)} k. - _Wesley Ivan Hurt_, Apr 20 2023
%e 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.
%t Total[Range[#,DivisorSigma[1,#]]]&/@Range[60] (* _Harvey P. Dale_, Feb 23 2023 *)
%Y Cf. A000203.
%K nonn,easy
%O 1,2
%A _Juri-Stepan Gerasimov_, Jul 04 2009
%E a(12), a(33), a(34) and others corrected by _R. J. Mathar_, Jul 06 2009
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