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A098683 Numbers n such that pi(n)=prime(d_1)*prime(d_2)*...*prime(d_k) where d_1 d_2 ... d_k is the decimal expansion of n. 3
123, 5224, 11166, 51174, 172451, 546322, 14355351, 23539612, 23539621, 24322837, 122924349, 4575242147, 42256772524, 283186883151, 623286236455, 665318971119, 665318971191 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

a(18) > 10^12. [From Donovan Johnson (donovan.johnson(AT)yahoo.com), Jul 12 2010]

EXAMPLE

122924349 is in the sequence because pi(122924349)=P(1)*P(2)*P(2)*P(9)*P(2)*P(4)*P(3)*P(4)*P(9) where P(i) is i-th prime.

MATHEMATICA

Do[d=IntegerDigits[n]; k=Length[d]; If[ !MemberQ[d, 0]&&PrimePi[n]==Product[Prime[d[[j]]], {j, k}], Print[n]], {n, 230000000}]

CROSSREFS

Cf. A097227, A098684, A098685, A160040.

Sequence in context: A160040 A163711 A068239 * A135479 A095761 A121917

Adjacent sequences:  A098680 A098681 A098682 * A098684 A098685 A098686

KEYWORD

base,more,nonn

AUTHOR

Farideh Firoozbakht (mymontain(AT)yahoo.com), Sep 24 2004

EXTENSIONS

Corrected the entries. - Robert G. Wilson v (rgwv(AT)rgwv.com), May 04 2009

a(13)-a(17) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Jul 12 2010

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Last modified February 18 00:14 EST 2012. Contains 206085 sequences.