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A235495 Numbers n such that pi(2n) divides n. 1
1, 2, 3, 4, 48, 50, 60, 504, 540, 546, 558, 561, 564, 567, 4204, 4212, 4220, 4228, 4232, 4236, 32270, 32290, 32305, 32310, 32325, 32345, 32350, 32355, 32360, 240426, 240432, 240504, 240510, 240516, 240522, 240528, 240534, 240540, 240546, 240648, 240678, 240684 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..59

EXAMPLE

48 is in the sequence because pi(2*48) = 24 and 24 divides 48.

MATHEMATICA

Select[Range[10^6], IntegerQ[#/PrimePi[2#]]&]

PROG

(PARI) is(n)=n%primepi(2*n)==0 \\ Charles R Greathouse IV, Jan 12 2014

CROSSREFS

Cf. A057809.

Sequence in context: A037429 A230452 A270478 * A257482 A023167 A177380

Adjacent sequences:  A235492 A235493 A235494 * A235496 A235497 A235498

KEYWORD

nonn

AUTHOR

Vincenzo Librandi, Jan 11 2014

STATUS

approved

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Last modified July 24 06:56 EDT 2021. Contains 346273 sequences. (Running on oeis4.)