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The sum of the divisors of prime(n)#-1 where p# is the product of all the primes from 2 to p inclusive.
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%I #9 Oct 28 2023 14:35:14

%S 1,6,30,240,2310,30030,518940,9943560,230876448,6551588160,

%T 200561595684,7471933410000,304250263527210,13082853940673340,

%U 618109122639794688,32589631537463089128,1922760350251477679196,117386696543681561301312,7906535060701218163040640

%N The sum of the divisors of prime(n)#-1 where p# is the product of all the primes from 2 to p inclusive.

%F a(n) = sigma(prime(n)#-1) = A000230(A057588(n)).

%e a(4)=240 because the divisors of 7#-1 = 209 are {1, 11, 19, 209}.

%p seq(numtheory[sigma](mul(ithprime(k), k=1..n)-1), n=1..30);

%Y Cf. A057588, A000230, A054989, A366809, A064145.

%K nonn

%O 1,2

%A _Sean A. Irvine_, Oct 23 2023