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 A143274 #11 Oct 23 2023 12:28:35 %S A143274 1,6,15,32,50,84,112,160,207,270,319,420,481,574,675,800,884,1044, %T A143274 1140,1320,1470,1628,1748,2016,2175,2366,2565,2828,2987,3330,3503, %U A143274 3808,4059,4318,4585,5040,5254,5548,5850,6320,6560,7056,7310,7744,8190,8556,8836 %N A143274 a(n) = n * A006218(n). %F A143274 a(n) = n * A006218(n), where A006218(n) = partial sums of d(n). Equals row sums of triangle A143273. %e A143274 a(4) = 32 = 4 * A006218(4), where A006218 = (1, 3, 5, 8, 10,...). %e A143274 a(4) = 32 = sum of row 4 terms of triangle A143273: (4 + 8 + 8 + 12). %o A143274 (PARI) a(n) = n*sum(k=1, n, n\k); \\ _Michel Marcus_, Mar 19 2016 %o A143274 (Python) %o A143274 from math import isqrt %o A143274 def A143274(n): return (-(s:=isqrt(n))**2+(sum(n//k for k in range(1,s+1))<<1))*n # _Chai Wah Wu_, Oct 23 2023 %Y A143274 Cf. A000005, A006218, A143273. %K A143274 nonn %O A143274 1,2 %A A143274 _Gary W. Adamson_, Aug 03 2008 %E A143274 More terms from _Eric M. Schmidt_, Feb 28 2014