A143090 - OEIS

%I #15 Nov 01 2024 12:45:01

%S 12,16,15,9,4,3,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,

%T 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,

%U 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0

%N Aliquot sequence starting at 12.

%H Dominika Závacká, Cristina Dalfó, and Miquel Angel Fiol, <a href="https://ceur-ws.org/Vol-3792/paper19.pdf">Integer sequences from k-iterated line digraphs</a>, CEUR: Proc. 24th Conf. Info. Tech. - Appl. and Theory (ITAT 2024) Vol 3792, 156-161. See p. 161, Table 2.

%F a(n+1) = A001065(a(n)). - _R. J. Mathar_, Oct 11 2017

%t NestList[If[#>0,DivisorSigma[1, #]-#,0]&,12,100] (* _Paolo Xausa_, Oct 16 2023 *)

%Y Cf. A001065.

%K nonn,easy,changed

%O 0,1

%A _N. J. A. Sloane_, Nov 30 2008