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 A090342 #10 Sep 16 2018 13:35:30 %S A090342 -4,-3,-2,-3,-1,-1,0,-5,-1,-6,2,-1,5,-8,0,-11,8,-2,6,-14,1,3,8,0,-1, %T A090342 -14,-1,-20,19,-4,12,-2,4,-18,-9,-6,26,-20,4,-32,26,1,18,-32,0,11,35, %U A090342 -9,-3,-41,9,1,40,-11,-15,-46,10,-30,26,-1,49,15,-3,-55,-3,-10,53,-50,14,-59,32,-1,50,21,-5,-56,5,6,36,-70,-2,21,38 %N A090342 Difference between the sums of the prime factors, including multiplicity, of n and those of n + 3. %H A090342 Harvey P. Dale, <a href="/A090342/b090342.txt">Table of n, a(n) for n = 1..1000</a> %F A090342 a(n) = A001414(n) - A001414(n+3). - _Wesley Ivan Hurt_, Aug 29 2016 %e A090342 a(24)=0 because 24=2*2*2*3, 27=3*3*3 and (2+2+2+3)-(3+3+3)=0. %t A090342 Join[{-4},#[[1]]-#[[4]]&/@(Partition[Table[Total[Flatten[Table[#[[1]], #[[2]]]&/@ FactorInteger[n]]],{n,2,90}],4,1])] (* _Harvey P. Dale_, Sep 16 2018 *) %Y A090342 Cf. A001414, A090340, A090341, A090343. %K A090342 sign %O A090342 1,1 %A A090342 Charles K. Layman (cklayman(AT)juno.com), Nov 25 2003