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%I #5 Jul 01 2020 22:29:36
%S 6,18,30,42,102,138,150,198,270,282,462,522,570,618,642,810,822,858,
%T 882,1050,1062,1230,1278,1290,1302,1482,1698,1722,1878,1950,1998,2082,
%U 2130,2142,2238,2310,2382,2550,2658,2730,2790,2802,2970,3258,3300,3330,3390,3462,3558,3582,3822,3918,3930,4002,4050,4158,4218,4230,4242
%N Average of those twin prime pairs p, q=p+2, for which A335884(p+1) >= A335884(p-1) and A335884(q-1) >= A335884(q+1).
%C For such twin prime pairs p, q, A335884(p) = A335884(q) = 1 + A335884((p+q)/2).
%o (PARI)
%o A335884(n) = { my(f=factor(n)); sum(k=1,#f~,if(2==f[k,1],0,f[k,2]*(1+max(A335884(f[k,1]-1),A335884(f[k,1]+1))))); };
%o isA335908(n) = (isprime(n-1)&&isprime(n+1)&&(A335884(n)>=A335884(n-2))&&(A335884(n)>=A335884(n+2)));
%Y Cf. A335884.
%Y Subsequence of A014574. Cf. also A335907.
%K nonn
%O 1,1
%A _Antti Karttunen_, Jul 01 2020
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