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A097644
Numbers n such that pi(n) = reversal(n).
0
51, 130, 370, 8201, 73270, 82080, 26113610, 4854248220, 37682961610
OFFSET
1,1
COMMENTS
This sequence has only two odd terms, i.e., 51 and 8201 and 10 divides all other terms. Next term is greater than 10^8.
EXAMPLE
26113610 is in the sequence because
pi(26113610) = 1631162 = reversal(26113610).
MATHEMATICA
Do[If[PrimePi[m]==FromDigits[Reverse[IntegerDigits[m]]], Print[m]], {m, 100000000}]
CROSSREFS
Sequence in context: A129298 A065010 A365834 * A353987 A044302 A044683
KEYWORD
base,nonn
AUTHOR
Farideh Firoozbakht, Aug 25 2004
EXTENSIONS
Two more terms from Giovanni Resta, Feb 06 2006
STATUS
approved