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 A138981 a(n) = Sum_{k=0..n} A138980(k). 2

%I

%S 1,4,9,16,27,40,57,76,99,128,159,196,237,280,327,380,441,508,579,652,

%T 731,814,903,1000,1101,1204,1311,1420,1533,1660,1791,1928,2067,2216,

%U 2367,2524,2691,2864,3043,3224,3415,3608,3805,4004,4215,4438,4665,4894

%N a(n) = Sum_{k=0..n} A138980(k).

%C By definition, every term is nonprime (i.e., is 1 or composite).

%Y Cf. A138980.

%K nonn

%O 0,2

%A _Leroy Quet_, Apr 05 2008

%E Extended by _R. J. Mathar_, May 21 2010

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Last modified December 2 13:44 EST 2022. Contains 358510 sequences. (Running on oeis4.)