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Number of primes in A339443 among the values of A339443(k) for k = 1..n.
1

%I #6 Jan 01 2021 12:02:51

%S 0,0,1,1,2,2,3,4,4,4,5,6,7,7,7,8,9,10,10,10,11,12,12,13,14,14,14,15,

%T 16,17,17,17,17,17,18,19,19,20,21,21,21,21,21,22,23,24,24,24,25,26,26,

%U 26,26,27,27,28,29,29,29,30,31,31,31,32,32,33,33,33,34,35,35,35,35,35

%N Number of primes in A339443 among the values of A339443(k) for k = 1..n.

%H <a href="/index/Par#part">Index entries for sequences related to partitions</a>

%F a(n) = Sum_{k=1..n} pi(c(k)) - pi(c(k)-1), where c = A339443.

%e a(12) = 6; The first 12 values of A339443 are 1, 1, 2, 1, 3, 1, 2, 2, 4, 1, 3, 2 (of which, 6 are prime).

%Y Cf. A000720, A339443, A340203.

%K nonn

%O 1,5

%A _Wesley Ivan Hurt_, Dec 31 2020