

A007597


Strobogrammatic primes.
(Formerly M4800)


13



11, 101, 181, 619, 16091, 18181, 19861, 61819, 116911, 119611, 160091, 169691, 191161, 196961, 686989, 688889, 1008001, 1068901, 1160911, 1180811, 1190611, 1191611, 1681891, 1690691, 1880881, 1881881, 1898681, 1908061, 1960961, 1990661
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OFFSET

1,1


COMMENTS

Primes which are invariant under a 180 degree rotation.


REFERENCES

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
C. W. Trigg, "Strobogrammatic Primes and Prime Rotative Twins", J. Rec. Math., 15 (1983), 281282.


LINKS

Table of n, a(n) for n=1..30.
C. K. Caldwell, The Prime Glossary, Strobogrammatic
Wikipedia, Strobogrammatic prime


MATHEMATICA

lst = {}; fQ[n_] := Block[{allset = {0, 1, 6, 8, 9}, id = IntegerDigits@n}, Union@ Join[id, allset] == allset && Reverse[id /. {6 > 9, 9 > 6}] == id]; Do[ If[ PrimeQ@n && fQ@n, AppendTo[lst, n]], {n, 2000000}]; lst (* Robert G. Wilson v, Feb 27 2007 *)


CROSSREFS

Cf. A000787.
Sequence in context: A089716 A084987 A083185 * A061247 A199328 A068188
Adjacent sequences: A007594 A007595 A007596 * A007598 A007599 A007600


KEYWORD

base,nonn


AUTHOR

N. J. A. Sloane, Robert G. Wilson v


EXTENSIONS

More terms from David W. Wilson


STATUS

approved



