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