%I #8 Jan 13 2019 03:11:01
%S 4,12,22,34,44,58,72,88,100,120,126,148,164,182,196,220,228,254,264,
%T 284,304,328,338,358,382,400,420,444,442,478,494,518,544,564,562,602,
%U 622,648,652,690,684,730,740,768,790,812,828,858,870,898,920,946,958,990
%N a(n) = Sum_{k=n^2+1..(n+1)^2-1} tau(k).
%F a(n) = A168011(n) - A168011(n-1) - A048691(n). - _R. J. Mathar_, Jan 25 2010
%p A168011 := proc(n) add( numtheory[tau](k),k=1..n^2+2*n) ; end proc: A048691 := proc(n) numtheory[tau](n^2) ; end proc: A171762 := proc(n) A168011(n)-A168011(n-1)-A048691(n) ; end proc: seq(A171762(n),n=1..80) ; # _R. J. Mathar_, Jan 25 2010
%t Array[n \[Function] Sum[DivisorSigma[0, k], {k, n^2 + 1, (n + 1)^2 - 1}], 200] (* J. Mulder (jasper.mulder(AT)planet.nl), Jan 28 2010 *)
%Y Cf. A000005, A048691, A168011.
%K nonn,easy
%O 1,1
%A _Giovanni Teofilatto_, Dec 18 2009
%E Definition corrected by _Giovanni Teofilatto_, Dec 19 2009
%E More terms from _R. J. Mathar_ and J. Mulder (jasper.mulder(AT)planet.nl), Jan 25 2010
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