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A175318 a(n) = Sum_{k<=n} A007955(k), where A007955(m) = product of divisors of m. 0

%I

%S 1,3,6,14,19,55,62,126,153,253,264,1992,2005,2201,2426,3450,3467,9299,

%T 9318,17318,17759,18243,18266,350042,350167,350843,351572,373524,

%U 373553,1183553,1183584,1216352,1217441,1218597,1219822,11297518,11297555,11298999,11300520

%N a(n) = Sum_{k<=n} A007955(k), where A007955(m) = product of divisors of m.

%e For n = 4, with b(n) = A007955(n), a(4) = b(1)+b(2)+b(3)+b(4) = 1+2+3+8 = 14.

%o (PARI) prd(n) = my(dn = divisors(n)); prod(i=1, #dn, dn[i]);

%o a(n) = sum(k=1, n, prd(k)); \\ _Michel Marcus_, Dec 09 2014

%Y Cf. A007955.

%K nonn

%O 1,2

%A _Jaroslav Krizek_, Apr 01 2010

%E Edited and more terms from _Michel Marcus_, Dec 09 2014

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Last modified July 30 09:18 EDT 2021. Contains 346359 sequences. (Running on oeis4.)