This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A343938 #7 Aug 09 2021 11:21:00
%S A343938 0,1,0,2,-1,1,-2,3,0,0,-3,2,-4,-1,-1,4,-5,1,-6,1,-2,-2,-7,3,-2,-3,0,0,
%T A343938 -8,0,-9,5,-3,-4,-3,2,-10,-5,-4,2,-11,-1,-12,-1,-1,-6,-13,4,-4,-1,-5,
%U A343938 -2,-14,1,-4,1,-6,-7,-15,1,-16,-8,-2,6,-5,-2,-17,-3,-7
%N A343938 Twice the number of prime factors of n minus the sum of prime indices of n, both counted with multiplicity.
%C A343938 A prime index of n is a number m such that prime(m) divides n. The multiset of prime indices of n is row n of A112798.
%F A343938 Totally additive with a(prime(k)) = 2 - k.
%e A343938 For n = 1050 we have 5 prime indices {1,2,3,3,4}, so a(1050) = 10 - 13 = -3.
%t A343938 Table[2*PrimeOmega[n]-Total[Cases[FactorInteger[n],{p_,k_}:>k*PrimePi[p]]],{n,100}]
%Y A343938 First appearances are the elements of A174090 except for 3.
%Y A343938 Positions of zeros are A340387.
%Y A343938 Positions of nonpositive terms are A344291.
%Y A343938 Positions of nonnegative terms are A344296.
%Y A343938 A001222 counts prime indices.
%Y A343938 A056239 adds up prime indices.
%Y A343938 A112798 lists prime indices.
%Y A343938 Cf. A001221, A003963, A061775, A275024, A279789, A299757, A302242.
%K A343938 sign
%O A343938 1,4
%A A343938 _Gus Wiseman_, Aug 04 2021