A340205 - OEIS

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A340205

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

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, 16, 17, 17, 17, 17, 17, 18, 19, 19, 20, 21, 21, 21, 21, 21, 22, 23, 24, 24, 24, 25, 26, 26, 26, 26, 27, 27, 28, 29, 29, 29, 30, 31, 31, 31, 32, 32, 33, 33, 33, 34, 35, 35, 35, 35, 35

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OFFSET

1,5

LINKS

Table of n, a(n) for n=1..74.

Index entries for sequences related to partitions

FORMULA

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

EXAMPLE

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).

CROSSREFS

Cf. A000720, A339443, A340203.