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Least initial term of a set of n consecutive primes {p_1 .. p_n} such that Sum_{k=p_1..p_2} d(k) = ... = Sum_{k=p_(n-1)..p_n} d(k), where d(k) is the number of divisors function A000005.
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%I #8 Jun 22 2022 21:41:18

%S 1867,105373,238820129,106695130613

%N Least initial term of a set of n consecutive primes {p_1 .. p_n} such that Sum_{k=p_1..p_2} d(k) = ... = Sum_{k=p_(n-1)..p_n} d(k), where d(k) is the number of divisors function A000005.

%C It doesn't matter if the primes are included in the sums or excluded as long as the symmetry is taken into account (d(prime) is always 2).

%e a(3) = 1867 = prevprime(A353552(1));

%e a(4) = 105373 = A353553(1);

%e a(5) = 238820129 = A353554(1).

%Y Cf. A000005, A000040, A133760, A353552, A353553, A353554.

%K nonn,hard,more

%O 3,1

%A _Karl-Heinz Hofmann_, May 27 2022