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%I #8 Jul 07 2014 07:33:49
%S 0,30,1797,132946,10034416,790688821,64867780292,5492352229154,
%T 475943074590494,41984058676639733,3755707610763952011,
%U 339758793864093720073,31019273006095379281810,2853680710328414627392965,264227600111858563511104972
%N Sum of the first 10^n terms in A097975. a(n) = sum_{m=1..10^n} t(m), where t(m) is the sum of the prime divisors of m that are greater than or equal to sqrt(m).
%C Does a(n+1)/a(n) converge?
%e The first 10^2 terms in A097975 sum to 1797, so a(2) = 1797.
%t s = 0; k = 1; Do[l = Select[Select[Divisors[n], PrimeQ], # >= Sqrt[n]&]; If[Length[l] > 0, s += l[[1]]]; If[n == k, Print[s]; s = 0; k *= 10], {n, 1, 10^7}]
%o (PARI) a(n) = sum(m=1, 10^n, sumdiv(m, d, d*isprime(d)*(d>=sqrt(m)))); \\ _Michel Marcus_, Jul 07 2014
%Y Cf. A097975.
%K more,nonn
%O 0,2
%A _Ryan Propper_, Jul 24 2005
%E a(2)-a(7) and the example corrected and a(8)-a(14) from _Hiroaki Yamanouchi_, Jul 07 2014
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