This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A129283 #18 May 14 2025 04:27:49 %S A129283 0,1,3,4,8,6,11,8,20,15,17,12,28,14,23,23,48,18,39,20,44,31,35,24,68, %T A129283 35,41,54,60,30,61,32,112,47,53,47,96,38,59,55,108,42,83,44,92,84,71, %U A129283 48,160,63,95,71,108,54,135,71,148,79,89,60,152,62,95,114,256,83,127,68 %N A129283 a(n) = (arithmetic derivative of n) + n. %H A129283 Reinhard Zumkeller, <a href="/A129283/b129283.txt">Table of n, a(n) for n = 0..10000</a> %F A129283 a(n) = A003415(n) + n. %F A129283 a(n) = A003415(n*A051674(k)) / A051674(k). %F A129283 a(A129284(n)) > 1, a(A129285(n)) > 1, a(A129286(n)) > 1. %F A129283 Sum_{k=1..n} a(k) ~ c * n^2 / 2, where c = 1 + Sum_{p prime} 1/(p*(p-1)) = 1 + A136141 = 1.773156... . - _Amiram Eldar_, May 14 2025 %p A129283 A129283 := proc(n) %p A129283 n+A003415(n) ; %p A129283 end proc: %p A129283 seq(A129283(n),n=0..40) ; # _R. J. Mathar_, Feb 04 2022 %t A129283 ad[n_] := Switch[n, 0|1, 0, _?PrimeQ, 1, _, Sum[Module[{p, e}, {p, e} = pe; n*e/p], {pe, FactorInteger[n]}]]; %t A129283 a[n_] := ad[n] + n; %t A129283 Table[a[n], {n, 0, 100}] (* _Jean-François Alcover_, May 23 2023 *) %o A129283 (Haskell) %o A129283 a129283 n = a003415 n + n -- _Reinhard Zumkeller_, Nov 01 2013 %Y A129283 Cf. A003415, A051674, A129284, A129285, A129286, A136141. %K A129283 nonn,easy %O A129283 0,3 %A A129283 _Reinhard Zumkeller_, Apr 07 2007