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%I #16 Oct 19 2019 03:20:14
%S 0,2,5,7,12,1,1,1,1,4,1,1,1,2,1,1,6,1,1,1,4,1,1,1,2,1,1,1,2,1,1,1,3,4,
%T 1,3,1,2,3,1,1,2,1,1,1,2,1,1,1,2,1,1,1,2,1,1,1,2,1,1,1,2,1,1,10,1,1,1,
%U 2,29,1,1,2,1,7,1,2,1,1,1,2,1,1,1,2,1,1,1,2,1,1,1,2,3,1,1,2,1,5,1,14,1,1
%N a(n) is the GCD of the sum of largest prime factors of numbers from 1 to n and of the sum of smallest prime factors of numbers from 1 to n.
%H Michael De Vlieger, <a href="/A088823/b088823.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = gcd(A088821(n), A088822(n)).
%p map(igcd@op, ListTools:-PartialSums([[0,0],seq([min,max](numtheory:-factorset(n)),n=2..N)])); # _Robert Israel_, Dec 16 2015
%t GCD @@@ Transpose[{Accumulate[Prepend[First /@ #, 0]], Accumulate[Prepend[Last /@ #, 0]]}] &@ Map[First /@ FactorInteger@ # &, Range[2, 103]] (* _Michael De Vlieger_, Dec 15 2015 *)
%Y Cf. A088821, A088822, A088824, A088825.
%K nonn
%O 1,2
%A _Labos Elemer_, Oct 22 2003
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