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A273974 Number of primes <= n-th Catalan number. 1
0, 0, 1, 3, 6, 13, 32, 82, 226, 651, 1939, 5946, 18637, 59736, 194898, 645742, 2167325, 7359262, 25237989, 87325031, 304549332, 1069685013, 3781189896, 13443608964, 48049822995, 172568075048, 622514907195, 2254799747130 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

LINKS

Table of n, a(n) for n=0..27.

FORMULA

a(n) = A000720(A000108(n)). - Michel Marcus, Nov 10 2016

MATHEMATICA

Table[PrimePi[CatalanNumber[n]], {n, 0, 27}]

PROG

(MAGMA) [#PrimesUpTo(Catalan(n)): n in [0..18]];

CROSSREFS

Cf. A000108, A054782, A277062, A277063.

Sequence in context: A018014 A162483 A187780 * A179928 A026538 A201951

Adjacent sequences:  A273971 A273972 A273973 * A273975 A273976 A273977

KEYWORD

nonn

AUTHOR

Vincenzo Librandi, Nov 10 2016

STATUS

approved

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Last modified October 28 09:43 EDT 2020. Contains 338052 sequences. (Running on oeis4.)