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A086609 Number of primes between consecutive partition numbers. 1
0, 1, 1, 1, 1, 1, 1, 2, 2, 3, 3, 5, 5, 6, 8, 10, 12, 14, 17, 21, 24, 30, 36, 44, 49, 63, 71, 87, 100, 120, 143, 164, 200, 226, 272, 318, 368, 432, 499, 593, 681, 792, 912, 1069, 1228, 1437, 1641, 1900, 2177, 2530, 2896, 3348, 3832, 4379, 5039, 5775, 6582, 7516 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,8

LINKS

Andrew Howroyd, Table of n, a(n) for n = 0..150

FORMULA

a(n) = A000720(A000041(n+1)) - A000720(A000041(n)).

PROG

(PARI) a(n)={primepi(numbpart(n+1)) - primepi(numbpart(n))} \\ Andrew Howroyd, Jan 05 2020

CROSSREFS

Cf. A000040, A000041, A000720.

Sequence in context: A325391 A179254 A304430 * A341140 A340285 A341462

Adjacent sequences:  A086606 A086607 A086608 * A086610 A086611 A086612

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Sep 11 2003

EXTENSIONS

Terms a(42) and beyond from Andrew Howroyd, Jan 05 2020

STATUS

approved

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Last modified June 13 11:42 EDT 2021. Contains 344992 sequences. (Running on oeis4.)