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%I #35 Oct 23 2023 17:41:28
%S 1,53,1471,29425,496623,7518850,106030594,1421760251,18362473634,
%T 230375375227,2824280446479,33978264556380,402439152166882,
%U 4703975577244852,54365786164534232,622220063695532731,7060841638683030355,79525016215415440837
%N Partial sums up to 10^n of A007425.
%H Henri Lifchitz, <a href="/A180365/b180365.txt">Table of n, a(n) for n = 0..23</a> (first 21 terms from Hiroaki Yamanouchi)
%F a(n) = A061201(10^n).
%o (PARI) a(n)=sum(k=1, 10^n, numdiv(k)*floor((10^n)/k));
%o vector(7, n, a(n-1)) \\ _Altug Alkan_, Sep 24 2015
%o (Python)
%o from math import isqrt
%o from sympy import integer_nthroot
%o def A180365(n): return (m:=integer_nthroot(t:=10**n,3)[0])**3+3*sum(-(s:=isqrt(r:=t//i))**2+(sum(r//k for k in range(1,s+1))<<1)-sum(t//(i*j) for j in range(1,m+1)) for i in range(1,m+1)) # _Chai Wah Wu_, Oct 23 2023
%Y Cf. A007425, A061201.
%K nonn
%O 0,2
%A _Andrew Lelechenko_, Jan 19 2011
%E One more term (a(16)) and typo in crossrefs fixed by _Andrew Lelechenko_, Apr 13 2011
%E a(17) from _Hiroaki Yamanouchi_, Jul 15 2014
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