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%I #11 Jan 01 2019 12:39:56
%S 2,5,7,11,13,16,21,23,25,31,35,37,39,42,49,51,53,55,58,60,65,73,75,77,
%T 80,82,84,86,88,97,99,101,105,107,113,115,117,119,121,124,134,136,138,
%U 140,144,147,149,151,153,155,157,160,162,164,166,168,179,181,188
%N Sum of the largest exponents A025479 of the first n perfect powers > 1.
%H Hugo Pfoertner, <a href="/A322969/b322969.txt">Table of n, a(n) for n = 1..10000</a>
%e a(1) = 2 because the first perfect power 4 = 2^2,
%e a(2) = 5: added exponent 3 from 8 = 2^3,
%e a(3) = 7: added exponent 2 from 9 = 3^2,
%e a(4) = 11: added largest exponent 4 from 16=2^4.
%t Union@ Accumulate@ Table[If[Set[e, GCD @@ #[[All, -1]]] > 1, e, 0] &@ FactorInteger@ n, {n, 4, 2400}] (* _Michael De Vlieger_, Jan 01 2019 *)
%o (PARI) my(s=0); for(k=1, 3^7, if(j=ispower(k), print1(s+=j, ", ")))
%Y Cf. A001597, A025479, A076408.
%K nonn
%O 1,1
%A _Hugo Pfoertner_, Jan 01 2019