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Terms k of A104210 for which abs(A003961(k)-(2*k)) is prime, where A003961 is fully multiplicative with a(prime(i)) = prime(i+1), and A104210 gives numbers m for which gcd(m,A003961(m)) > 1.
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%I #9 Dec 23 2024 09:42:09

%S 6,15,35,77,646,1334,2294,5681,6293,78793,600677,2255002,2482402,

%T 4564166,8702275,16798717,17747807,22197526,236981285,302764377,

%U 1287983157,2111098886,2295003595

%N Terms k of A104210 for which abs(A003961(k)-(2*k)) is prime, where A003961 is fully multiplicative with a(prime(i)) = prime(i+1), and A104210 gives numbers m for which gcd(m,A003961(m)) > 1.

%C The definition entails that both abs(A379231(n)) and A151799(abs(A379231(n))) divide a(n).

%C If it exists, a(24) > 2^32.

%H <a href="/index/Pri#prime_indices">Index entries for sequences related to prime indices in the factorization of n</a>.

%Y Cf. A003961, A104210, A151799, A252748, A379230, A379231.

%K nonn,more,new

%O 1,1

%A _Antti Karttunen_, Dec 23 2024